The left engine of 257-seat Boeing 777 burst into flames on the runway at McCarran International Airport in Las Vegas shortly after 4:00 pm (2300 GMT) while it was about to depart for London's Gatwick Airport with 159 passengers and 13 crew members on board, according to the airport authorities.
Heavy black smoke and orange flames could be seen pouring from under the plane's wings, sending passengers fleeing quickly from the aircraft and across the tarmac before about 50 firefighters doused the aircraft in minutes.
The authorities said seven passengers were treated for minor injuries.
Fire officials said paramedics on the scene were also evaluating some passengers.
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 underway.
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.
One of the airport's runways was shut down but operations continued on the other three runways, officials said.
Las Vegas' airport is the ninth-busiest in the US and had nearly 43 million passengers last year.
The airport has been taking steps to accommodate more international travellers seeking direct flights to Europe and Asia, including adding new gates to accommodate wide-body double-decker jets..
Image: A British Airways passenger jet is shown after a fire at McCarran International Airport in Las Vegas. Photograph: Steve Marcus/Reuters
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