Several people have died after a tour bus overturned and left a major highway in western New York.

The bus was carrying 52 people, including the driver, at the time of the crash this afternoon on Interstate 90 in Pembroke, about 30 miles east of Buffalo.

The New York State Police (NYSP) said there were multiple fatalities and injuries, including children.

A state trooper told reporters near the crash site that some people were still trapped in the wreckage and rescues were underway.

He added that some passengers were "ejected" from the bus when it rolled.

The police were in contact with the bus operator, which was not immediately identified.

The tour bus was hired from New York City where it was returning to from Niagara Falls, the NYSP said.

A police statement added: "Several witnesses observed the bus lose control, enter the median, then cross to the southern shoulder and overturn.

"The investigation is ongoing. Additional information will be released as it becomes available."

The Erie County Medical Centre, an adult trauma centre in Buffalo, said it had received seven patients as of about 2pm local time, CBS reports.

New York Governor Kathy Hochul said she had been brief on the "tragic tour bus incident".

"My team is coordinating closely with New York State Police and local officials who are working to rescue and provide assistance to everyone involved," she wrote to X.