All of those killed in the blast in Dera Bugti area, around 350 kilometres east of the provincial capital Quetta, were civilians, District Coordination Officer Abdul Samad Lasi said.
No one has claimed responsibility for the attack but Lasi held an anti-government nationalist group responsible for it. He alleged that Bugti tribe had planted landmines in the area to restrict the movement of the people and one of the landmines hit the passenger coach.
"The authorities are facing a lot of problems due to landmines," he told 'Geo' television, adding that private militia of the chief of Bugti tribe, Nawab Akbar Bugti, had also established a camp to "shelter criminals."
But, the security forces have dismantled the camp. No one has been arrested so far in connection with the blast, Lasi said. He said security forces have been deployed for safety of the gas pipelines in the area.
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