Vladimir Putin has ordered a thorough investigation of the mine explosions
Russian Prime Minister Vladimir Putin has visited a mine where blasts left 90 people dead or missing. He met victims' families and promised an investigation.
The death toll from the explosions has risen to 47, including miners and rescue workers, while 43 miners are still unaccounted for.
The initial gas blast at Raspadskaya mine in Siberia happened on Saturday.
Rescuers were sent into the coal mine, but many were killed when a second explosion destroyed the main air shaft.
Teams of rescuers have since been racing to find survivors amid fears over the risk of further explosions and rising water in parts of the mine.
Stern-faced and dressed in black, Mr Putin told victims' families on Tuesday that he shared their suffering.
"I want you to know that we're only talking about formalities here and that government support goes without question."
The prime minister ordered a thorough investigation into the explosions. "We must know what has led to such a large number of victims, such a big tragedy," he said.
Many of Russia's mines have poor safety records, and there have been calls for standards to be raised.
Mr Putin also visited some of those wounded in the explosions in hospital.
Some 83 miners injured in the accident remained in hospital on Tuesday, a senior Russian official said.
The explosions were so powerful that even buildings above ground were badly damaged.
The mine, in the town of Mezhdurechensk in the Kemerovo region, is about 3,500km (1,900 miles) east of Moscow, and produces about eight million tons of coal a year, its website says.
Kemerovo is part of the major coal-producing Kuzbass region.