BERLIN (Reuters) - A bus carrying over 30 tourists from Australia, Canada and the United States crashed into a truck filled with car tires near Heidelberg, Germany on Thursday, leaving nine people seriously injured, local police said.

Five rescue helicopters and seven ambulances raced to the scene in the small southwestern town of Hockenheim, about 20 km from Heidelberg, to carry off injured passengers, a police spokesman said. He said the road was shut for several hours.

Broadcaster SWR said a total of 35 people were injured in the accident, including the drivers of the bus and the lorry, and four people were in critical condition.

The police spokesman could not immediately confirm those details.

It said the bus shifted into the opposing lane and collided with the truck while approaching an on-ramp to the A61 highway.