OXFORD, ENGLAND, JULY 19 -- A double-decker bus carrying gifted teenage students from the United States overturned on a highway outside Oxford today, killing two and injuring 56 other people, police said.

Some passengers were thrown out windows, some crawled from the bus, some were pulled free by rescuers, and at least three were trapped inside for an hour, authorities said. Four people suffered serious injuries.

"It was a scene of utter chaos and mayhem," said ambulance superintendent Robin Finlayson. "There were girls and boys trapped in the coach and others strewn up the bank . . . many had crush injuries."

The bus was taking about 60 American students and staff to an arts festival when the bus went out of control as it turned off the A40 highway near Wheatley, about six miles east of Oxford, said Chief Inspector John Wheeler of the Thames Valley Police.

Chief Inspector Laurie Fray said two students had died -- a boy and a girl -- and a total of 56 were injured.

The gifted students from all over the United States have been taking a four-week summer course at Oxford University's Magdalen College. The program is organized by the Oxford Advanced Studies Program in New York, U.S. coordinator Paul Beresford-Hill said. Most of the students were between their junior and senior years in high school, he said.

David Watson of the Bus and Coach Council identified the driver as Gan Sharma, 40, of Reading, who had worked for the Bee Line 14 years.

Marilyn Whiteman, a cook at a nursing home, said the bus had passed her a mile before the crash. "He was traveling at between 80 and 85 mph, and the bus was swaying all over the place," she said.