As many as 40 people may still be trapped in the rubble of a Russian apartment block that partially collapsed in a gas explosion, killing at least seven people.
The blast is thought to have been caused by a gas leak and damaged 48 apartments in a nine-storey building in Magnitogorsk, an industrial city in the Urals some 1700km east of Moscow, the emergencies ministry said.
President Vladimir Putin flew into Magnitogorsk late on Monday afternoon, visiting the injured in hospital and meeting with local authorities, state television showed.
Putin looked on as rescue workers toiled in temperatures of -22C to locate people trapped under the debris.
Emergencies Minister Yevgeny Zinichev said at a meeting with Putin there were thought to be between 36 and 40 people under the rubble.
After reporting four casualties earlier in the day, Zinichev said another three bodies had been discovered but could not be removed.
"We are working carefully because there is a risk that the building will collapse," news agencies quoted Zinichev as saying.
Health Minister Veronika Skvortsova told state television that the chances of finding survivors were fading as the day wore on.
The blast tore through the building around 6am local time on Monday, when many residents were asleep.
There have been several similar incidents in Russia in recent years due to ageing infrastructure and poor safety regulations regarding gas usage.
