Iván C.M., from Zaragoza was thought to have been dead for at least two weeks when his dismembered body was discovered, since it was the strong stench of decomposed flesh that alerted his neighbours to the fact that something was wrong.

Initially investigated by the homicide team of the National Police, it was thought that the 33-year-old ex-Armed Forces member had been the victim of a grisly murder.

But after combing his flat, they found strong evidence to suggest that he had tied an explosive cord around his neck in order to sever his own head clean off.

The cord, which is commonly used in the Army, is designed to slice pieces of concrete, rock or thick pipes in two, using one swift move by tying the rope around the object and blowing it up to produce a clean cut.

Police found no other weapons or explosives in his flat, which was apparently 'very dirty and untidy', and no suicide note.

He is believed to have hidden behind the sofa and covered his head with a towel to cut out the noise.

Neighbours in the block and other acquaintances say the deceased was suffering from a very deep depression.

He had been serving abroad in war zones and it is believed that some of his disturbing experiences on the front line could have had a very profound and long-lasting psychological effect on him.

Additionally, the separation from his wife and very young son may have exacerbated his mental state.

Sources close to the victim say he avoided people like the plague and fled from any form of communication with his neighbours.

He had left the Army as a result of his depression.

One neighbour said Iván used to go up and down the stairs in the dark to avoid attracting attention and having to talk to people, and never attended meetings of the community of property owners for the block where he had bought the flat three or four years ago.