XALAPA, Mexico (AP) — A tour bus and a semi-trailer collided Wednesday on a mountain road in the Mexican state of Veracruz, and the bus rolled over and caught fire, killing at least 21 people and injuring 30, officials said.

Roberto Hernández, the civil defense director for Nogales township, said the bus turned onto one side and the ground blocked its exit doors.

Initial reports said 20 people were killed, but state civil defense director Guadalupe Osorno said one injured person died later.

Authorities said both vehicles were westbound when they apparently collided in a mountainous area known as Cumbres de Maltrata. Both caught fire.

In April 2006, a bus carrying religious pilgrims in the same area ran off the highway and tumbled down a steep ravine, killing 65 people.