Officials said the person jumped a perimeter fence before the aircraft struck them during takeoff.
DENVER, CO — A Frontier Airlines jet bound for Los Angeles struck and killed a person on a Denver International Airport runway late Friday, forcing pilots to stop the aircraft and crews to evacuate passengers after an engine fire, airport officials said.
The crash brought a sudden emergency to one of the nation’s busiest airports and opened a federal and local investigation into how a person reached an active runway. Denver International Airport said Frontier Flight 4345 reported hitting a pedestrian at about 11:19 p.m. Friday, May 8. Officials said the person was not believed to be an airport employee and had not been identified by Saturday.
The flight was taking off from Denver for Los Angeles International Airport when the crew reported the strike. Airport officials said the person jumped a perimeter fence and was hit about two minutes later while crossing the runway. Audio from air traffic control captured the pilot telling the tower, “We just hit somebody. We have an engine fire.” The pilot also reported “231 souls” on board and said an “individual was walking across the runway.” Emergency crews responded while the aircraft remained on the runway. The Denver Fire Department quickly extinguished the brief engine fire, officials said.
The aircraft carried 224 passengers and seven crew members, according to reports from airport and airline officials. Passengers evacuated on emergency slides and were bused back to the terminal. Twelve people reported minor injuries during the evacuation, and five were taken to area hospitals, officials said. The condition of those hospitalized was not immediately released. Frontier Airlines said smoke was reported in the cabin and the pilots aborted takeoff. It was not immediately clear whether the smoke was caused by the strike, the engine fire or another issue. The airline said the passengers were later placed on a new Frontier flight, and the majority had departed Denver by Saturday morning.
Denver International Airport said Runway 17L would remain closed while the investigation continued. The airport, known by its DEN code, has a large airfield northeast of downtown Denver and handles heavy commercial traffic throughout the day and night. The incident raised immediate questions about perimeter security, runway surveillance and the timeline between the fence breach and the aircraft strike. Officials said the person entered the airfield only minutes before the collision. They had not released the person’s name, age, hometown or reason for being near the runway. Authorities also had not said whether the person acted alone or how far they traveled after crossing the fence.
The National Transportation Safety Board is investigating the aviation accident, with support expected from the Federal Aviation Administration, airport officials, Frontier Airlines and local law enforcement. Denver police are also involved because the death happened on airport property. Investigators are expected to review runway video, radio transmissions, aircraft data, crew statements, emergency response records and the condition of the airport perimeter. The aircraft, an Airbus A321, will likely remain part of the inquiry while officials examine the engine and other systems affected by the strike. No charges had been announced Saturday, and officials had not released a schedule for reopening the runway.
The emergency unfolded quickly for passengers, who had just begun the takeoff roll when the pilots stopped the jet. Some passengers described hearing a thud before the plane slowed and crews began preparing the evacuation. The use of emergency slides can lead to scrapes, sprains and other minor injuries, and officials said medical teams evaluated passengers after they reached the terminal. Frontier Airlines said it was cooperating with authorities. Denver International Airport said emergency crews responded to the scene and that passengers were taken from the runway area to the terminal after the evacuation.
The fatal strike remained under investigation Saturday as officials worked to identify the person killed and determine how the security breach occurred. Runway 17L stayed closed pending the investigation, while airport and airline operations continued with delays and adjustments after the late-night emergency.
Author note: Last updated May 9, 2026.