A pensioner claims he has found Adolf Hitler's secret atom bombs inside tunnels dug by the Nazis underneath a mountain valley in central Germany.

Peter Lohr, 70, claims to have found five large metal objects in a cave in the Jonas Valley in Thuringia state, of which at least two are 'atomic bombs'.

Mr Lohr is certain that the objects are weapons of mass destruction manufactured by the Nazis towards the end of the Second World War.

'Proof': Peter Lohr, 70, shows the result of his 3D radar research in the Jonas Valley, which he claims shows five large metal objects in a cave, of which at least two are 'atomic bombs'

The former mechanical engineer claims the shape of the objects match that of a nuclear bomb, The Local reports.

Using a radar with 3D technology, Mr Lohr claims to be able to prove that the objects are atomic bombs, warning that they could cause a nuclear disaster.

'The metal's been lying there for 71 years. At some point it will decay and then we will have a second Chernobyl on our hands' he said.

The centre of the Jonas Valley was a scene of secret military construction towards the end of the Second World War, with thousands of concentration camp prisoners forced to dig tunnels under the mountains.

It is not known what purpose the tunnels were meant to have as it was never completed.

Sure thing: Mr Lohr is certain that the objects are weapons of mass destruction manufactured by the Nazis towards the end of the Second World War

Claims: There have been several people claiming to have found proof of Hitler's 'atomic bombs' over the years

The tunnel system stretches for miles underneath the mountain, with thousands of caves, bunkers and storerooms, and it is believed that it was intended to be the Alamo of the Third Reich leadership.

The Jonas Valley was liberated by American troops in April 1945, and US authorities have since classified all 1945 documents relating to Ohrdruf for a minimum of 100 years.

This is not the first time rumours of a Nazi nuclear bomb has surfaced.

Last year, a documentary called The Search for Hitler's Atom Bomb,' quotes sealed records from Russia and America said to prove the Nazis were close to creating a weapon of mass destruction.