The scene outside the mine
The number of people now known to have died after two gas explosions at a coal mine in Russia has risen to 43, emergency officials say.
Dozens of others are missing after the blasts at Raspadskaya mine in Siberia.
The emergency situations ministry said it was not clear whether any trapped miners were still alive.
Those killed in the accident included both miners and rescuers, who were already underground when a second explosion happened.
Emergency Situations Minister Sergei Shoigu said on Monday that methane levels had dropped enough to make it safe for rescue workers, though rising water in the mine posed another threat.
Rescuers would have only until Wednesday to try to reach 13 people thought to be in the affected areas, he added.
Poor safety record
Dozens of people were injured in the incident.
Many of Russia's mines have poor safety records, and there have been calls for standards to be raised.
More than 300 people were underground when the first explosion happened just before midnight on Saturday and most were brought safely to the surface. Reports blamed the blast on methane gas.
The second explosion came about three hours later and contact with a team of 20 rescuers was lost.
The governor of Siberia's western Kemerovo region, Aman Tuleyev, has taken charge of the rescue operation.
He said the second blast had destroyed the main air shaft, causing more injuries, and there was a risk of more explosions.
Russian media reported that Prime Minister Vladimir Putin had flown to the area to visit some of those injured in the accident.
Earlier, he had described the situation at the mine as "tragic".
"The saddest thing is that we cannot send in additional rescuers now as it is very dangerous due to the lack of ventilation," he was quoted as saying by AFP news agency.
"But we cannot sit on our hands and must do everything to save people."
State TV pictures showed that the explosions had been so powerful that buildings on the surface had been badly damaged.
The mine, about 3,500km (1,900 miles) east of Moscow, produces about eight million tons of coal a year, its website says.
Kemerovo is part of the major coal-producing Kuzbass region.