At least nine people were killed when a tanker truck collided with a coach in Mexico.

After the collision early Saturday morning (local time) on an expressway near the municipality of Hidalgo, both vehicles burst into flames, the police in the northeastern state of Tamaulipas said on Twitter.

It is being determined whether the driver of the tanker truck was to blame for the accident.

According to media reports, one of the truck's two fuel tanks had come loose and crashed into the bus.

Tamaulipas chief of civil protection, Pedro Granados, said according to the Reforma newspaper.

The number of dead could rise to 20 – the bodies were burned.

According to the police, the bus was traveling from the central Mexican state of Hidalgo to the city of Monterrey, according to initial information.