At 4:30 pm local time on August 4, water from a nearby reservoir flooded the underground Mir mine. The same day, Sergei Ivanov, chief executive of the diamond mining company Alrosa, departed for the accident site at the town of Mirny. The flooding of the pumping stations resulted in some 250,000 cubic meters of water flowing into the mine.

"Mine rescue brigades continue their search effort in galleries 210 and 310 where load-haul dump machines can be used to help clear tunnels from silt, debris and large ore fragments. Some galleries are out of reach. Over the last 24 hours, rescue workers cleared more than 200 meters of passages, and a total of more than seven thousand meters were inspected as part of the rescue operation," the company said in a statement released on its website.

A crisis center was set up immediately after the accident and is still working. According to Yegor Borisov, head of the Republic of Sakha (Yakutia), accident victims are receiving psychological and medical assistance. Borisov pointed out that Alrosa management pledged to provide for the social security of workers at the affected mine by guaranteeing them pay and employment. Participants in the rescue operation are entitled to double pay.

During the meeting with Yegor Borisov, Russian Security Council Secretary Nikolai Patrushev stressed the need to inspect other mines. "Accidents like this one should not happen. The situation should be controlled by identifying in a timely manner risks that could lead to emergencies and preventing them," Patrushev said, as quoted by Interfax news agency.

According to the commander of National Mine Rescue Center's rapid response team Nikolai Myasnikov, the roadway profile changed when the water was pumped out, which complicated rescue efforts. Clay pulp and curved metal components are also an obstacle, and debris has to be removed by hand. "The sections covered by debris that could be blocking us from the trapped miners are 240 and 480 meters long," Myasnikov told Interfax news agency. Rescue workers are working around the clock in the mine in 6 to 8 hour shifts of 60 to 80 people, waist deep in water, which also makes it harder for them to move around.

A criminal case was opened in connection with the flooding of the mine. The investigators are interrogating company employees and inspecting the accident site.

"A criminal case was opened under Article 216 of the Criminal Code of the Russian Federation (violation of safety rules in mining operations). The injured will undergo forensic medical examination, and documents were taken from the company, including workers' guidelines," the Investigative Committee of the Russian Federation said in a statement.

Alrosa head Sergei Ivanov said on August 6 that the company will adjust its production plans following the accident, TASS reported. Before the accident, Alrosa planned to recover and sell 39 million carats of diamonds in 2017, and Alrosa management did not exclude revising plans upwards in autumn.

"Production volumes will be adjusted by August 19 as part of the review of the 2017 budget following the accident at Mir mine," he said.

Alrosa shares lost more than 1 percent after the company announced it wanted to review its production plans following the Mir mine accident, RIA Novosti reported, citing data from the Moscow Stock Exchange. As of 12:40 pm, Moscow time, Alrosa shares were down 1.59 percent at RUB 81.93.