1 missing USF doctoral student found dead, roommate charged with murder: Sheriff
In these photos released by the University of South Florida Police Department, Zamil Limon and Nahida Bristy are shown. (University of South Florida Police Department)
(TAMPA, Fla.) — The remains of one of the two missing University of South Florida doctoral students were discovered by investigators Friday and his roommate was arrested, authorities said.
Hisham Abugharbieh, 26, has now been charged with two counts of first-degree murder with a weapon in the deaths of Zamil Limon and Nahida Bristy, the Hillsborough County Sheriff’s Office announced on Saturday.
Investigators found the remains of Limon on the Howard Frankland Bridge in Tampa Friday morning, Joseph Maurer, of the Hillsborough County Sheriff’s Office, told reporters Friday.
The search for Bristy continues, the office said.
Investigators have been searching for Limon and fellow USF doctoral student Bristy since they went missing on April 16.
“We are still actively searching for Nahida,” he told reporters during a news conference Friday.
Maurer said investigators received a 911 call for a domestic violence disturbance around 9 a.m. Friday at a residence where Limon’s roommate, Abugharbieh, had barricaded himself.
Abugharbieh was previously interviewed by police during their investigation into the disappearances, Mauer said.
Following a brief standoff, the suspect surrendered, Maurer said. He was seen exiting the home with nothing but a towel wrapped around his waist.
Abugharbieh was initially charged with unlawfully holding or move a dead human body in unapproved conditions, failure to report a death to the medical examiner or law enforcement (intent to conceal), tampering with physical evidence, false imprisonment and battery, the sheriff’s office said.
The suspect is not a current USF student or employee, school officials said.
Abugharbieh will have his first court appearance on Saturday morning.
USF President Moez Limayem said in a statement Friday that there is “no ongoing threat to the safety of the university community.” He expressed “deep sadness” over Limon’s death and prayed for Bristy’s “safe return.”
The cause of Limon’s death is being determined, Maurer said. He had no further details about Bristy’s condition.
Marine and dive teams were searching near the Howard Frankland Bridge for Bristy, the sheriff’s office said.
Limon and Bristy, both 27, were last seen at separate locations in the Tampa area on April 16, according to the USF Police Department.
On Thursday, officials received new information to warrant upgrading their status from missing to endangered, which indicates they are at risk of physical injury or death, the Hillsborough County Sheriff’s Office said.
The sheriff did not provide any more details about the investigation or search efforts.
Limon and Bristy are friends, and a mutual acquaintance reported them missing, campus police said.
Limon was last seen at his Tampa residence at approximately 9 a.m. on April 16, according to police.
He had attended the university since fall 2024 to study geography and environmental science and policy, school officials said.
Bristy was last seen at the USF Tampa campus at the Natural & Environmental Sciences Building at approximately 10 a.m. on April 16, police said.
She has attended the university since fall 2025 to study chemical engineering, school officials said.
Anyone with information on her whereabouts is urged to call the University of South Florida Police Department at 813-974-2628.
-ABC News’ Meredith Deliso contributed to this report.
A Frontier Airlines Airbus A320neo plane, owned by the Bank of Utah Trustee, taxis to a gate at Denver International Airport (DEN) on March 23, 2026 in Denver, Colorado. (Photo by Al Drago/Getty Images)
(LOS ANGELES) — A Frontier Airlines flight taking off for Los Angeles from Denver International Airport on Friday night struck an individual walking on a runway, according to the airline and airport officials.
The incident occurred shortly after 11:00 p.m. local time on Runway 17L, the airline said in a statement early Saturday. There were 224 passengers and 7 crew members on board, Frontier said.
The person struck was at least partially consumed by one of the engines, an official confirmed to ABC News, causing a brief engine fire.
According to air traffic control audio obtained by ABC News, pilots reported an engine fire and smoke inside the aircraft following the incident.
Transportation Secretary Sean Duffy said Saturday the victim had breached airport security, deliberately scaled a perimeter fence and ran onto the runway.
The person was struck by the plane during takeoff at high speed, Duffy said.
Preliminary reports are that 12 were injured and five were taken the hospital, according to the secretary.
“Emergency response and investigation are ongoing,” the Denver International Airport said earlier. “The NTSB has been notified. Runway 17L will remain closed while the investigation is conducted.”
A source briefed on the incident told ABC News that airport security was inspecting the east perimeter fence on Saturday morning for gaps and the person struck did not appear to be connected to the work occurring on a parallel runway.
“We are investigating this incident and gathering more information in coordination with the airport and other safety authorities,” Frontier Airlines said. “We are deeply saddened by this event.”
Local law enforcement handles airport security and is investigating the breach with support from the Federal Aviation Administration and Transportation Security Administration, Duffy said.
In this U.S. Coast Guard handout, the Coast Guard investigates aircraft wreckage on the Potomac River on January 30, 2025 in Washington, DC. (Petty Officer 1st Class Brandon Giles/ U.S. Coast Guard via Getty Images)
(WASHINGTON) — The National Transportation Safety Board on Tuesday presented a cockpit visual simulation demonstrating what contributed to the deadly mid-air collision between an Army helicopter and an American Airlines jet near Washington, D.C., last year.
The simulation indicates it was very difficult for both aircraft to see each other before the January 2025 crash that occurred as the jet was landing at Ronald Reagan National Airport, killing 67 people, according to the NTSB.
The first video shows the last three minutes before the collision from the viewpoint of the right seat of the helicopter.
Around 8:46:15, a magenta circle with a label “Flight 5342” appears just above the horizon on the right side of the upper portion of the screen. The label “Flight 5342” fades out about 8:46:35. The magenta circle tracks the lights of Flight 5342 and remains visible until the airplane becomes visually recognizable about a minute later.
After a Traffic Alert and Collision Avoidance System warning indicated in the transcript, the local controller on the ATC recording is heard asking the pilots if they have the CRJ (Flight 5342) in sight and the pilots confirm they do. It remains unclear what they thought they had in sight. There was only one controller working both the helicopter and plane traffic, the NTSB said.
The simulation screen goes black at the moment of the collision.
The second animation shows the viewpoint of pilots from Flight 5342 as the plane approaches the runway to land. According to the cockpit voice recorder transcript shared by the NTSB, the last words about one second before the crash from both the first officer and the captain were “oh” and “ohhh ohhhh” as the animation shows the helicopter colliding with the plane.
About 90% of wreckage from both aircraft was recovered by the NTSB.
A third animationshows what the local controller from the DCA tower saw at the time of the crash as they were handling the air traffic and issuing instructions. Based on the recordings, the NTSB said Flight 5342 was not warned by the controller of the nearby helicopter at any point. A conflict alert came 26 seconds before the collision between the two aircraft as they were 1.6 miles apart, according to the NTSB.
According to the NTSB, the local tower said they were concerned about the close proximity of the helicopter and Flight 5342.
“This coupled with the conflict alert that was active at the time, the controller should have issued a safety alert, which would have included updated traffic advisory information and an alternate course of action if feasible, neither were done. In this case, had a safety alert been issued, it would have increased the situation awareness of both crews and alerted them of their closing proximity to one another. Additionally, a timely safety alert may have allowed action to be taken by one or both crews to avoid avert the collision,” NTSB investigator Brian Soper said at the hearing.
NTSB Chair Jennifer Homendy also said that a $400 GPS device known as ADSB-In could have prevented the DCA crash. The NTSB has recommended ADSB-In be required in aircraft 17 times since 2006, but the FAA has repeatedly disregarded the recommendation, she said.
The system would have alerted the American Airlines crew 59 seconds before the crash that they were going to collide, and the helicopter crew would have been alerted 48 seconds before the crash, the NTSB chair said. The Army has since installed the system.
DCA controller overwhelmed
The controller working the night of the crash was handling both helicopter and plane traffic and had been doing so for four hours, NTSB investigators said.
A human behavior investigator said the controller’s mental awareness had diminished over time. He should have given a definitive warning of the impending collision and he should have given clear avoidance instructions, the investigator said.
NTSB investigators said the last communication between the helicopter and the controller where they asked the pilot if they have the AA5342 in sight was “not a safety alert by definition, but it was an attempt to de-conflict.”
Ninety seconds before the collision, the local controller working in the tower became overwhelmed as he was handling aircraft both on ground and in the air. On the night of the collision, the controller was working two controller positions. This is a routine practice which is usually done later at night when the aircraft volume goes down.
The NTSB said, “keeping the local control and helicopter control positions combined on the night of the accident, increased the local controller’s workload and reduced his situation awareness.”
Investigators said the controller could have asked for the positions to be decombined because of being overwhelmed, but it would have taken at least a couple of minutes before anyone else could take over. Additionally, the assistant local controller and the supervisor overseeing operations at the time could have served as an extra set of eyes to help the local controller.
However, Homendy revealed that at the time, the assistant controller was writing down information on helicopters and the supervisor did not exhibit situational awareness as they learned during the interview that the supervisor only recalled one helicopter in the area at the time when there were five.
Following the crash, the NTSB issued recommendations for better training to be provided for controllers so they can recognize safety issues and threats in the environment.
NTSB chair’s concerns
Ahead of Tuesday’s hearing, Chair Homendy said she fears that some of the agency’s safety recommendations, which will be issued at the conclusion of the hearing, may once again go unimplemented.
“Of course I’m concerned. We have 300 aviation recommendations that still haven’t been implemented. Those recommendations were issued because somebody died or was injured, and they have not been implemented yet. So here we are again,” Homendy told ABC News.
“So yes, at the end of this, I am concerned that we’re going to issue recommendations and that they won’t be implemented,” Homendy said. “I can tell you, and anyone who knows me knows I vigorously advocate for the implementation of our recommendations. I don’t care when it is. Could be 50 years later, as I did with positive train control, and I will not hold back on these.”
At Tuesday’s hearing, NTSB investigators will present their investigative findings to board members and the public. NTSB board members, including Homendy, will then question investigators and the parties to the investigation.
At the end of the hearing, the board members will vote on the probable cause of the crash and the agency’s safety recommendations. The NTSB can only make recommendations and does not have the authority to enforce them, therefore they are not always adopted.
Though a formal final report will be released two weeks after the hearing, this hearing will mark the end of what Homendy described as “one of the most complex investigations” conducted by the agency, which they had aimed to conclude by the first anniversary of the mid-air collision.
Homendy told ABC News the investigation “was not easy and it was definitely not straightforward.”
“We will start in one direction and then take it in a different direction, depending on what we’re finding, and then we’ll exclude things that didn’t have anything to do with the investigation. But we have to do our due diligence to make sure that we’re tracking all of that down, all that evidence to support that it wasn’t a factor, while also looking at the issues that were,” Homendy said.
Homendy said the helicopter altimeter discrepancy is what surprised her the most in this investigation.
“The altimeters I did not see coming, that we would have some problems with how the altimeters were reading,” Homendy said.
During last year’s three-day investigative hearing, investigators said they found discrepancies in the altitude data shown on radio and barometric altimeters on Army helicopters after conducting test flights following January’s accident.
It is likely that the helicopter crew did not know their true altitude due to notoriously faulty altimeters inside this series of Black Hawks, according to the investigation. At their closest points, helicopters and planes flew within 75 feet of each other near DCA, an astonishingly close number. During the hearings, the NTSB was told Army Black Hawks can often have wrong readings and a margin of error of +-200 feet.
Another key focus of Tuesday’s hearing is the close proximity of the helicopter route to the runways at Reagan National Airport. According to the NTSB, which cited FAA surveillance data, there were over 15,000 close-proximity events between helicopters and commercial aircraft at DCA between October 2021 and December 2024.
Homendy said warnings about the close proximity were raised by people, but they were ignored.
“Years ago, that hot spot was identified and [people] repeatedly tried to say that the helicopter route needed to be moved, and nobody listened. It was like the ultimate in government bureaucracy,” Homendy said.
“They were completely ignored. Told it couldn’t be done, not responded to, said it would probably be too political. Those are quotes from our interviews, but they went nowhere.”
At last year’s hearing, FAA officials cited “bureaucratic process” as a deterrent to addressing these issues.
Other topics expected to be discussed include the approval of helicopter routes near DCA, the experience level of the air traffic controllers working in the tower at the time of the crash, the visibility study, and the testing of the barometric altimeters.
When asked what stays with her from this investigation, Homendy pointed to a personal item recovered with the wreckage.
“In the hangar, we had the Black Hawk laid out. We had the wreckage laid out for 5342 and on the side next to 5342 there were some personal effects, and a lot of people mentioned different things, but every time I passed, there was a brown teddy bear, just eight inches maybe, and it was muddy and dried mud, dried water, and I just kept looking at the teddy bear, and that’s the thing that sticks with me,” Homendy said.
Kilmar Abrego Garcia (R) and his wife Jennifer Vasquez Sura (L) attend a prayer vigil before he enters a U.S. Immigration and Customs Enforcement (ICE) field office on August 25, 2025 in Baltimore, Maryland. (Anna Moneymaker/Getty Images)
(NEW YORK) — A federal judge in Tennessee will hear arguments Thursday over whether the government is being vindictive in pursuing a human smuggling case against Kilmar Abrego Garcia.
The hearing comes after the judge, Waverly Crenshaw Jr., canceled the trial in the case in December and wrote in a court order that there was enough evidence to hold a hearing on the question of vindictive prosecution.
The government is currently blocked from deporting Abrego Garcia, who was released from immigration detention in December. In a separate case last week, a federal judge ruled that Immigration and Customs Enforcement cannot re-detain him because his 90-day detention period had expired and the government lacked a viable plan for his deportation.
The Salvadoran native, who had been living in Maryland with his wife and children, was deported in March to El Salvador’s CECOT mega-prison — despite a 2019 court order barring his deportation to that country due to fear of persecution. The Trump administration claimed he was a member of the criminal gang MS-13, which he and his attorneys deny.
He was brought back to the U.S. in June to face human smuggling charges in Tennessee, to which he pleaded not guilty.
After being released into the custody of his brother in Maryland pending trial, he was again detained by immigration authorities before being released in December.
