Muktan: At least 25 people, most of them school children, were killed in a head-on collision between an overcrowded bus and a truck near the central Pakistan town of Lodhran on Friday, police said.

The bus was heading out of Lodhran when it rammed into the truck on the opposite side of the road. Those killed included 20 students and four women, police said.

More than 30 people were injured.

"The bus was full to capacity. Some students were sitting on the roof," said Lodhran's police chief Khurram Ali.