At least 11 people were killed and many more wounded on Monday when a powerful bomb ripped through a passenger bus in Pakistan’s southwestern Baluchistan province

At least 11 people were killed and many more wounded on Monday when a powerful bomb ripped through a passenger bus in Pakistan's southwestern Baluchistan province, local officials said.

A bomb disposal official said a large explosive device was planted at the rear of the bus, which was carrying laborers working in central Quetta to their homes on the outskirts of the city.

The blast ends a recent lull in attacks in the regional capital, which for years has been a frequent target of extremists and separatist insurgents.

"The death toll from the bus explosion is 11, while 22 people are injured," Akbar Hussain Durrani, home secretary of Baluchistan province, told AFP.

A senior police official and a doctor at the city's main hospital confirmed the causalities.

Chaotic scenes unfolded in the emergency department of Provincial Sandeman Hospital as the dead and wounded were brought in, their blood staining stretchers and beds, while panicked relatives clamored for help.

Doctor Noor Baluch, a police surgeon, said 10 people were already dead by the time their bodies arrived in hospital, while 23 others had been wounded.

"Later an injured person died in hospital. Four of the wounded people are still in critical condition," he said.

Commander Abdul Razzaq from the bomb disposal squad said the bomb was in the rear of the vehicle.

"The explosive device weighed up to 6 kilograms and was planted in the back of the bus. Most likely it was a time device," he told AFP.