This first giant crater measuring around 262ft and found in far northern Siberia is believed to have been caused by rising temperatures in the area. Recent helicopter video footage of the first hole, in the Yamal region, reveals a mound of loose dirt that appears to have been thrown out of the hole with water inside

Three craters that appeared in Siberia over the summer are thought to have been caused by huge underground gas explosions and could be 'the key' to the mystery of the Bermuda Triangle, according to scientists.

The holes – one in Taymyr peninsula and two in Yamal, known to locals in Siberia as 'the end of the world' – were the topic of much speculation, provoking suggestions that they were the product of alien invaders, meteorites, missiles or even a man made hoax.

Now scientists from the Trofimuk Institute of Petroleum-Gas Geology and Geophysics in Novosibirsk believe that they are the result of large underground gas explosions and could explain the disappearances in the infamous Bermuda Triangle.

"The main element - and this is our working theory to explain the Yamal crater - was a release of gas hydrates. It turned out that there are gas hydrates both in the deep layer which on peninsula is several hundred metres down, and on the layer close to the surface," said scientist Vladimir Potapov.

Gases, methane in particular, are trapped in frozen hydrates below the permafrost (soil at or below the freezing point of water), and under some oceans, which researchers believe could be strong enough to bring down an aircraft or sink a ship, if they erupted.

"There is a theory that the Bermuda Triangle is caused by gas hydrates," said the Trofimuk Institute's deputy head, Igor Yeltsov. "They start to actively decompose with methane ice turning into gas. It happens in an avalanche-like way, like a nuclear reaction, producing huge amounts of gas. That makes the ocean heat up, and ships sink in waters which are infused with huge amounts of gas. This leads to the air becoming supersaturated with methane, creating an extremely turbulent atmosphere, leading to aircraft crashes".