The 157 passengers aboard British Airways Flight 2276 were settled into their seats for the 10-hour flight from Las Vegas to London when the aircraft's left side engine caught fire.
Those aboard fled down emergency slides and across the tarmac as flames leaped from the British Airways Boeing 777-200 and dark black smoke billowed.
Reggie Bugmuncher, of Philadelphia, was charging her phone and waiting at a gate Tuesday for her flight from McCarran International Airport when she heard people saying, "Oh, my God." She looked out and saw "bursts of flames coming out of the middle of the plane."
"Everyone ran to the windows and people were standing on their chairs, looking out, holding their breath with their hands over their mouths," Bugmuncher said.
The plane's emergency slides deployed and passengers quickly fled. She said it was a "bit more orderly" than she would have expected given the dramatic nature of the fire and smoke.
Firefighters stationed at the airport reached the plane two minutes after getting reports of flames, and within another three minutes, everyone inside the plane had escaped.
After firefighters extinguished the flames, emergency vehicles could be seen surrounding the aircraft, which was left a sooty gray from the smoke and fire retardant.
Federal Aviation Administration spokesman Ian Gregor said the plane's left engine caught fire and an investigation was under way. The National Transportation Safety Board was collecting information about the incident, said Eric Weiss, a spokesman for the agency in Washington.
Clark County Deputy Fire Chief Jon Klassen said the cause of the fire wasn't clear yet, but the fire didn't appear to breach the cabin.
Fire officials said 14 people were taken to Sunrise Hospital by early Tuesday evening for minor injuries, most a result of sliding down the inflatable chutes to escape.
Airport Chris Jones said passengers were taken by the airline to hotels but he had no additional information on their travel plans.
The Federal Aviation Administration delayed flights to Las Vegas from some airports for more than two hours after the fire to slow the flow of planes while the disabled Boeing 777 made two of the airport's four runways inaccessible. One of the runways reopened about 2 1/2 hours after the fire.
British Airways spokeswoman Caroline Titmuss didn't answer questions about the incident in an email exchange but said "safety is always our priority."
Titmuss said in an email that the airline was "looking after customers" but didn't elaborate. She said the airline would release more information later.
Las Vegas' airport is the ninth-busiest in the U.S. and had nearly 43 million passengers last year. The airport has been taking steps to accommodate more international travelers seeking direct flights to Europe and Asia, including adding new gates to accommodate wide-body double-decker jets.