Frontier jet strikes pedestrian on Denver runway, passengers evacuate after engine fire

A Frontier Airlines jet struck a pedestrian on an active Denver runway Friday night, forcing investigators to confront the central safety question in the case: how someone reached runway 17L during a takeoff at one of the nation’s busiest airports.

Frontier Flight 4345, an Airbus A321 bound for Los Angeles International Airport, was carrying 224 passengers and seven crew members when the collision happened at about 11:19 p.m. local time at Denver International Airport. Airport officials said the aircraft then had a brief engine fire that was extinguished by the Denver Fire Department, and pilots reported smoke in the cabin before aborting the takeoff.

Passengers evacuated through emergency slides and were bused to the terminal. Officials reported one minor passenger injury. The condition of the pedestrian was not immediately disclosed.

The runway was closed while investigators worked the scene, and the Federal Aviation Administration said it was investigating the incident. The National Transportation Safety Board was notified and later said it was coordinating with the FAA, Denver International Airport operations and local law enforcement as they gathered information about what led to the collision and the fire.

Frontier said it was investigating the incident with airport and safety authorities and said it was deeply saddened by the event. Denver police said the investigation remained active and they had no additional information to provide immediately.

The episode landed at a moment of heavy traffic for the airport, which was expected to see about 450,000 travelers move through its terminals over the weekend. That scale only sharpened the urgency around the unanswered access-control question at the heart of the incident: how a pedestrian got onto a live runway during takeoff, in the dark, at an airport that handles millions of passengers each year.