The former head of a Siberian diamond mine owned by Alrosa where eight men were killed in a flood two years ago was found dead in a pre-trial detention center on Tuesday, a day after he was arrested, Russian investigating authorities said.
A regional branch of the federal Investigative Committee said there were indications the death of Alexei Burkser at the center in the remote Yakutia region in eastern Siberia had been suicide. Russian state-controlled Alrosa declined to comment.
Burkser had run the Mir diamond mine in Yakutia, which flooded in August 2017, killing eight miners. He was detained on Monday on suspicion of violating safety rules.
Alrosa is the world's largest producer of rough diamonds in carat terms. Together with Anglo American's De Beers unit, it produces about half of the world's rough diamonds.
The underground mine, which produced 8% of Alrosa's output, flooded when water poured into the shaft from an open-cast mine above it.
Investigators believe there had been signs that water was coming into the mine a month prior to the accident, the Interfax news agency reported.
They suspect that Burkser and Alexander Mann, Mir's former acting chief engineer who was also detained on Monday, were aware of the situation but did not suspend operations or ensure employees were not endangered, Interfax said.