At least 11 coal miners died of suffocation in Balochistan’s Sanjdi area, Chief Mine Inspector Abdul Ghani said on Monday.
He said the colliers, hailing from Swat Valley in Khyber Pakhtunkhwa, died after the leakage of poisonous gas in the coal mine.
The official said the bodies of the miners have been retrieved and are being dispatched to their respective native areas.
The affected coal mine has been sealed, he added.
Interior Minister Mohsin Naqvi expressed sorrow over the death of 11 miners and offered his condolences to the families of the deceased.
“We are deeply saddened by the loss of precious human lives in the tragic incident,” an official quoted the interior minister as saying.
In March this year, twelve miners were killed and eight rescued after an explosion rocked the private coal pit in the mining region of Khost, 80 kilometres (50 miles) east of Quetta, trapping 10 people about 800 feet (244 metres) below ground.
The province's chief inspector of mines had said that 20 miners had been inside the mine when a methane gas explosion took place overnight.
Coal deposits are found in the western areas of Pakistan that sit near the Afghan border and mine accidents are common, mainly due to gas build-ups.
Mine workers have complained that a lack of safety gear and poor working conditions are the key causes of frequent accidents, labour union officials have said in the past.