Scientists say there is growing evidence that rising temperatures were catalyst for massive unexplained holes in ground.
High levels of ‘fire ice’ trapped in permafrost may turn Russia into a global leader of new gas sources.
Satellites show giant hole ringed by 20 'baby craters'.
Haunting beauty of massive hole as scientists examine frozen lake formed after giant blowout.
Reindeer herders find more craters in the far north in a deepening puzzle for scientists.
Renowned scientist says temperatures could 'rise twice faster' in Yakutia than the rest of the world.