A Chinese court has jailed a mine-owner and four of his employees over a blast in 2005 which killed 171 people in the north-east province of Heilongjiang.
The explosion destroyed the mine's ventilation system
Ma Jinguang, owner of the Dongfeng Coal Mine in Qitaihe City, was given six years and the others received between three and a half and five years.
It was not clear from proceedings at the court in Xinxing if the five convicted would lodge appeals.
The blast was one of the deadliest on record in China.
Ma was convicted of neglecting regulations and failing to ensure work safety in the mine.
According to the Chinese state news agency, the explosion on 27 November also injured 48 people and caused economic losses of about 43m yuan ($5.9m).
Ma was arrested shortly after the blast and it is unclear why it took so long for him to go on trial.
The coal dust explosion at the Dongfeng mine destroyed its ventilation system.
Accidents remain widespread in China's mines, despite a much-publicised government safety campaign.