Media playback is unsupported on your device Media caption Footage from the scene shows the damaged bus, and wreckage strewn across the road

At least 17 people have been killed in a bus bombing near the north-western Pakistani city of Peshawar, officials say.

The vehicle was carrying government employees back home in the Gulbela area, some 15km north-east of the city.

More than 70 passengers were on board, police said.

Peshawar, the main city of Khyber Pakhtunkhwa province, has been hit by numerous bomb and gun attacks blamed on Taliban insurgents in recent years.

Initial reports say the bomb was planted in the back of the bus.

Officials told the BBC that at least 34 people had been injured in Friday's blast. No group has so far claimed responsibility.

Police say that the bomb was planted specifically to kill government employees.

The head of Peshawar's bomb disposal unit said that between 10kg and 15kg (22lb to 33lb) of explosives were used in the device.

On Sunday a twin-suicide bombing outside a church in Peshawar in Pakistan killed at least 81 people.

It was one of the worst attacks on Christians in the country. Militants linked to the Pakistani Taliban said they carried out the bombing.

At least 20 people were killed and nearly 40 were injured when another bus carrying government workers was bombed in the same area in June 2012.