New thermal-imaging surveillance footage has captured the moment a person walks onto a runway at Denver International Airport before being struck and killed by a Frontier Airlines jet. The collision occurred at 11:19 p.m. Friday night as Flight 4345, bound for Los Angeles, was accelerating for takeoff. “We’re stopping on the runway. Uh, we just hit somebody… we have an engine fire,” the pilot told air traffic control, in a recording released by ATC.com. In subsequent communications, the pilot added: “I think we hit someone. An individual was walking across the runway.” The impact triggered an engine fire on the Airbus A321 and sent smoke into the cabin, prompting the flight crew to abort departure and evacuate 224 passengers and seven crew members via emergency slides. Photos from the scene appeared to show blood on the plane’s engine. Shortly before the incident, an individual climbed a fence on to the runway, according to transportation officials.…