RIO DE JANEIRO (AP) — A bus carrying employees of a textile company and a truck collided on a highway in Brazil's Sao Paulo state early Wednesday, killing 40 people, officials said.

Rescuers were helping the wounded and passengers caught in the wreckage of the vehicles in the municipality of Taguaí, about 350 kilometers (217 miles) from the city of Sao Paulo. Television images showed shards of glass, destroyed bus seats and pieces of the vehicles’ bodies strewn on the highway.

“There is no clear indication about what caused the accident, and it is being investigated,” Sao Paulo Gov. João Doria said in a press conference. He said all the resources of his government would used to help the victims and their families.

A police spokesperson told TV Globo that so far the death toll stood at 37 and Sao Paulo firefighters later said on their official Twitter account that 40 people had been killed.