Over 600 miners of Barapukuria Coal Mining Company Limited in Dinajpur left the project area Sunday night protesting against unbearable working conditions.
They alleged that their Chinese employer forced them to stay inside the project area despite the poor living conditions there and tortured them in the name of maintaining health safety.
Their departure affected coal production in Parbatipur upazila of Dinajpur, which supplies coal to Barapukuria Coal-fired 525MW Power Plant.
Some of the miners returned to work yesterday, after the authorities filed a case over the incident.
Chinese contractor CMC-XMC consortium is responsible for coal production and development of the mine.
Rabiul Islam, president of the Miners' Union at Barapukuria Coal Mining Company Limited (BCMCL), said around 1,100 local miners became unemployed after March 26, 2020, due the pandemic.
There were only 300 Chinese miners at the mine, who continued production in small volumes. The nearby Barapukuria Coal Fired 525MW Power Plant used the produced coal to generate electricity until September, he added.
In September, the authorities began to let the local miners inside the mine if they tested negative for coronavirus.
On September 12, about 400 local miners returned to the mine. Over 200 others joined later, he said, adding that the rest of the miners, however, remained unemployed.
He alleged that the miners were forced to stay in three small rooms and no one was allowed to see their family members in the last seven months, he added.
"In the last seven months, I lived in a bathroom," miner Abdur Rahim said.
Although they had suffered so much, they were not being paid regularly, said Shahinur Rahman, another miner.
The miners started demonstrating inside the project area on Friday evening while the sacked miners also demonstrated outside the premises.
Khaled Mohammad Zaki, deputy commissioner of Dinajpur, held a meeting with the coalmine authorities and the miners, but failed to stop the miners from leaving on Sunday night.
Meanwhile, the mine authorities filed a case with Parbatipur Police Station triggering a wave of panic among the miners.
Rabiul said police have picked up five miners.
Contacted, BCMCL Managing Director Kamruzzaman admitted that the environment inside the mine was "tough". He added that the miners kept violating the health guidelines.