According to police, the bus carrying more than 60 passengers was moving from Shakargarh to Rawalpindi to attend a wedding ceremony.

On the way when the bus reached Massa Kuswal area, the cylinder of the bus exploded, resulting in a fire that burned most of the passengers to death.

Twelve people have been killed and several others injured. There are women and children among the dead. Some dead bodies are beyond recognition.

"The bodies are badly burnt and it is difficult to identify them," said a rescue official.

Dozens of passengers sustained injuries. The injured were shifted to hospitals in Gojar Khan and Rawalpindi.

Police said that the bus caught fire after cylinder exploded.