(Reuters) - A tour bus with about 50 passengers overturned on a Delaware highway on Sunday, leaving one woman dead and sending the others to hospital with injuries ranging from mild to severe, state police said.
Rescue teams backed by medical helicopters pulled trapped people through the windows of the bus, which flipped over at around 4:20 p.m. on a highway in Bear, about 12 m (19 km) south of Wilmington, Delaware State Police Sergeant Paul Shavack said.
It was unclear what caused the accident. No other vehicles were involved, officials said.
A woman was killed after she was ejected from the bus and then trapped under the overturned motor coach.
Two children were hurt, but their condition was unknown. Three to five other people were in critical condition, said Shavack, who described the vehicle as a single-deck tour bus.
At least 49 other people on the bus were taken to local hospitals with non-life threatening injuries, he said.
It was still unclear where the bus was headed and where it began its trip, Shavack said.
"We are interviewing the driver to try and determine what happened and where it was going," he said.
The bus company was identified by officials as AM USA Express, with offices in New York City's Chinatown, a hub for motor coach transport across the northeastern United States.
There was no reply to telephone calls to a number listed as AM USA Express' office.
(Reporting by Victoria Cavaliere in Seattle; Editing by Fiona Ortiz, Sandra Maler and Clarence Fernandez)