No serious injuries were reported among the 298 passengers and 18 crew when the incident occurred at Phoenix Sky Harbor International Airport at about 8 p.m. Arizona time (11 p.m. EDT), Phoenix Fire Department Capt. Shelly Jamison said.
About 15 people who were on board Flight 288 were evaluated for minor scrapes and bruises, but only one person was taken to a hospital with shoulder pain.
The jumbo jet had just pushed back from the gate when smoke was reported in the cabin, Jamison said. When fire crews arrived minutes later, the passengers and crew had already used escape slides to leave the jet and were on the tarmac next to the terminal.
Fire crews found light smoke in the cabin and in the cargo compartment, but no fire was discovered, Jamison said. No official cause has been determined, but she said fire crews on the scene believed the smoke and smell were likely caused by an electrical problem.
British Airways and the airport sent a bus to take the passengers back to the terminal.
KTVK-TV quoted one passenger as saying smoke was seeping out from under his seat, while a female passenger described an an acrid odor that didn't smell like smoke.
Airport operations were not affected.
"There were minor injuries obviously -- scrapes and bruises related to the evacuation, but other than that I don't have concrete numbers," airport spokeswoman Alisa Smith said.
British Airways has one daily nonstop flight from Phoenix to London's Heathrow airport that departs in the evening. Airline spokesman John Lampl said there were three pilots and 15 flight attendants on board.
"We'll put up the passengers (overnight) and hopefully they'll send a replacement plane in the morning," Lampl said.