Attaullah Khan, the director of disaster management, said methane gas had caused the explosion in a mine 35 miles east of Quetta city, capital of Baluchistan province.
"We have retrieved 11 bodies," Mr Khan said, adding that over a dozen labourers were still trapped in the mine.
Rescue work was in process, chief inspector of mines Iftikhar Ahmad said.
Accidents are frequent in the province's mines and are mainly due to inadequate safety measures.
It came on the same day that rescuers battled to reach five coal miners who were trapped nearly a mile underground in southern Poland after an earthquake.
The 3.4 magnitude quake hit the Borynia-Zofiowka-Jastrzebie mine on Saturday morning, trapping seven miners at a depth of about 900 metres (2,950 feet), state miningoffice WUG said.
Two had been reached by mid-afternoon and rescuers were thought to be within 150 metres of the remaining five, the chief executive of mine owner JSW, Daniel Ozon, told a news conference.
The two rescued miners were in a "relatively good condition" and could walk unaided, he said.
There were about 250 people working in the mine at the time of the quake, JSW said. The missing miners were from a team of 11 that were drilling a new tunnel. Four had managed to escape by themselves.
The rescue operation was earlier hampered by high levels of methane, which reached a concentration of up to 58 per cent.
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