A chilling picture has emerged of how knife murderer Christodoulos Sotiriou made guns secretly in his Camden Town bedroom for 10 years

Sotiriou, 43, of Camelot House in Camden Park Road, pleaded guilty on Monday at Blackfriars Crown Court to 11 separate charges of making and possessing weapons. He is due to be sentenced next month.

It has now been revealed that he spent his days creating an arsenal of deadly weapons, reading white extremist literature and practising counter-surveillance techniques.

He was previously sentenced to life in prison in 1991 for murdering Muswell Hill photographer Dietmar Kirchner in the changing rooms at Hornsey Swimming Pool with a commando knife.

The Austrian’s wife, former Warner Bros film boss Maj Britt Kirchner, was told of her husband’s death while she waited with Warren Beatty and Madonna at the premier of the film Dick Tracey.

After serving 10 years behind bars Sotiriou was released, at which point he told the National Probation Service he was moving to Cyprus. As a result they released him from all licence restrictions.

Unbeknown to anyone he stayed at the same home in Camden where he lived “under the radar” and busied himself with his sinister hobby of making guns.

Camden police officers were alerted in January this year when the UK Border Agency intercepted a parcel which included a bullet mould addressed to Sotiriou. Although bullet moulds are not in themselves illegal, the parcel was flagged up on the system because of his murder conviction.

Detective Sergeant Mark Richards, who was later commended for his team’s investigation, visited Sotiriou’s home in January this year.

There he discovered manuals on how to make bombs, a large amount of counter-surveillance and white supremacist literature, as well as heavy duty metalwork machinery.

It was here, in the very flat where he had lived when he murdered Austrian-born Dietmar Kirchner, that he set about manufacturing his deadly arsenal, simply ordering gun parts on the internet and converting them using techniques he had learned during a metalworking course in prison.

Speaking outside court, DS Richards said: “He was very jittery – completely on edge. He was incredibly agitated, nervous and unpredictable in his behaviour.

“There was a rucksack in his bedroom which contained muddy clothing, a fold-up spade, an Ordnance Survey map of Epping Forest and a hand held GPS Garmin.

“This was downloaded and it showed that he had been through Epping Forest and had saved it in his favourites.”

The co-ordinates led police to two separate caches hidden deep in the forest in Essex.

In the first stash, which was buried about a foot beneath the surface of the soil, were two Baikal handguns and a Brocock handgun, 32 single shot guns, an improvised short-barrelled shotgun and a Sten Mark Two submachine gun capable of firing 550 rounds per minute.

In the second horde, about 200 yards away buried on the other side of a forest path, officers discovered the components of 6,500 hollow-tipped bullets – which are banned under international law because of the horrific injuries they cause when they ‘mushroom’ on impact.

During his first police interview Sotiriou, who is described by police as highly intelligent, and a “loner”, refused to answer questions.

But after the forest find, he admitted the guns were his and was returned to jail. Back at his home in Camden, in something resembling a grisly monument, Sotiriou had kept a series of mounted press cuttings detailing the coverage of the murder he committed 20 years ago.

After Sotiriou’s guilty plea this week, DS Richards said: “It is unknown what Christodoulos Sotiriou intended to do with these weapons. However, we have ensured through committed intelligence-led policing, that this arsenal of weapons will never reach the streets of Camden.”

Sotiriou is due to be sentenced on November 25 at Blackfriars Crown Court, when legal representatives will try to establish what his motives were.