The death toll in a coal mine collapse due to a methane gas accumulation and explosion rises to 11 after rescuers recovered seven more dead bodies, an official said.

Twelve workers were trapped when the coal mine collapsed in the Sanjdi area, about 40 kilometres from Quetta in the Balochistan province, on Wednesday evening.

In three days of rescue work, 11 bodies were recovered until Saturday night with rescue workers still searching for the last worker inside the collapsed structure, Abdullah Shawani, the head of the province's mining department, said.

“There are little chances of the last worker surviving for so long in the collapsed mine,” Shawani said.

“The incident occurred due to a buildup of gas, which caused an explosion and the mine to cave in,” Balochistan government spokesperson Shahid Rind said.

He said full-scale rescue operations were ongoing but the progress was slow due to the presence of toxic gas and debris.

An investigation is on to ascertain whether proper mining regulations were followed, he said.

Pir Muhammad Kakar, one of the leaders of the mines workers association, said the incident resulted from non-implementation of mining regulations by the owner of coal mines and blamed officials at the mines department for the incident.

Kakar demanded strict action against these officials.

Coal mine collapses and death of workers happens frequently in the coal-rich western Balochistan known for hazardous working conditions and poor safety standards.

In March last year, at least 12 miners were killed in a gas explosion at a coalpit in Harnai.

In May 2018, 23 people were killed and 11 wounded after two neighbouring coal mines collapsed in Sanjdi while 43 workers also died in 2011 when gas explosions triggered a collapse in another Balochistan colliery.

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