The funnel is a perfectly formed cone, say locals who are mystified at how it was formed. Its depth is estimated at between 60 and 100 metres and its diameter - more than four metres. Picture: Local residents

Millions of people around the world glimpsed the first giant hole after it was revealed by The Siberian Times here and on The Siberian Times TV here.

Now news has emerged of two new similar formations in the permafrost, prompting more intrigue about their creation.

Theories range from meteorites, stray missiles, a man-made prank, and aliens, to an explosive cocktail of methane or shale gas suddenly exploding. The version about melting permafrost due to climate change, causing a release of methane gas, which then forces an eruption is the current favorite, though scientists are reluctant to offer a firm conclusion without more study.

First pictures from the big crater near Bovanenkovo gas field. Theories range from meteorites, stray missiles, a man-made prank, and aliens, to an explosive cocktail of methane or shale gas suddenly exploding. Pictures: Andrey Naumenko, 'Yamal-Region'

The second is in the Yamal Peninsula - known to locals as 'the end of the world' - like the first. It is some hundreds kilometres from the first, which is close to a huge gas extraction plant at Bovanenkovo. This new crater in the Taz district, near the village of Antipayuta, has a diameter of about 15 metres.

A deputy of the regional parliament - or duma - Mikhail Lapsui has examined this latest phenomenon.

'I flew by helicopter to inspect this funnel on Saturday 19 July,' he said. 'Its diameter is about 15 meters. 'There is also ground outside, as if it was thrown as a result of an underground explosion.

'According to local residents, the hole formed on 27 September 2013. Observers give several versions. According to the first, initially at the place was smoking, and then there was a bright flash. In the second version, a celestial body fell there.'

The Chief Scientist of the Earth Cryosphere Institute, Marina Leibman, told URA.RU website: 'I have heard about the second funnel on Yamal, in Taz district, and saw the pictures.

'Undoubtedly, we need to study all such formations. It is necessary to be able to predict their occurrence. Each new funnel provides additional information for scientists.'

This new crater in the Taz district, near the village of Antipayuta, has a diameter of about 15 metres. Pictures: Google maps, press service of the Governor YaNAO

The third crater and hole is in the Taymyr Peninsula, to the east of Yamal, in Kransoyark region. It was accidentally discovered by local herders, inhabitants of the northern village of Nosok.

The funnel is a perfectly formed cone, say locals who are mystified at how it was formed. Its depth is estimated at between 60 and 100 metres and its diameter - more than four metres.

The herders almost fell into the hole which lies on a pasturing route. They took pictures of the hole which were sent to scientists at the Norilsk Taimyr Explorers' Club.

Experts - geologists, ecologists, and historians - have not come to a consensus about the origin of the funnel, say reports in the region.

'It is not like this is the work of men, but also doesn't look like natural formation,' said one account.

The herders almost fell into the hole which lies on a pasturing route. They took pictures of the hole which were sent to scientists at the Norilsk Taimyr Explorers' Club. Pictures: Google maps, Local residents

Further study is planned of this hole.

The first hole is around 70 metres deep with an icy lake at its bottom.

Please see our reports on the first hole here and here.