Pakistan bus crash kills children in Punjab province Published duration 27 September 2011

media caption The wreckage of the bus crash

At least 26 people, mostly children, have been killed after a bus went off the road and plunged into a ravine in Pakistan, police say.

The bus was carrying students returning from an excursion when the incident happened on a motorway south-east of the capital Islamabad late on Monday.

The police said mechanical failure caused the crash.

Pakistan has one of the world's worst records for traffic accidents, blamed on poor roads and faulty vehicles.

The police said that the bus fell into the ravine after its brakes failed.

The accident happened in Kalar Kahar, Punjab province, about 160km (100 miles) south-east of Islamabad.

Correspondents say that it is one of the steepest parts of Pakistan's only motorway.

Twenty-two of the 26 people killed where students from a private school.

The driver, his assistant and the deputy-headteacher from the school were among the dead, police officer Chaudhry Salim told the AFP news agency.