Malcolm Constable took his own life by shooting himself in the garden of his brother's home in Priest Avenue, Canterbury

A man believed to have been connected to Britain's biggest cash heist has killed himself at the Canterbury home of his brother.

Father-of-two Malcolm Constable, 58, used a double-barrelled shotgun in the back garden of the house in Priest Avenue on the London Road Estate.

His body was found by his brother Derek, 65, who owns the house.

Derek said Malcolm had been feeling the pressure from his links to the infamous robbery of £53million from a Securitas depot in Tonbridge in February 2006.

It is thought he might have been involved in handling some of the stolen money.

Derek said: "It was a serious crime, a multi-million pound heist, and so I think this might have had something to do with it.

"you get criminals who are petty and do things because of drink or drugs, but this was massive stuff..." – derek constable

"You get criminals who are petty and do things because of drink or drugs, but this was massive stuff. He's still my brother though."

Malcolm was found in the back of Derek's garden at lunchtime on Thursday, February 7, but details of the incident are only just beginning to emerge.

Derek had gone out at 8.40am and returned to find his brother lying on the ground near a shed at the very back of the garden.

Malcolm, who owned a shotgun licence, had used a weapon bought from Ashford just two days before.

Derek said: "I came back to find him in the back garden.

"We had a gun cabinet, which you couldn't open without two people there. So it looks like he went out, bought this gun, smuggled it into the house and then waited for his opportunity.

"I'm still struggling with what I saw."

Derek said some 20 police vehicles and 50 officers attended the scene after the discovery.

Police are not treating the death as suspicious and have passed their findings to the coroner.

They said they have no record of him being involved in the Securitas raid seven years ago to the day, February 21.

Malcolm, who mainly worked in the building trade, grew up with his three brothers and two sisters at the Priest Avenue house before marrying Christine, with whom he has two daughters.

His funeral takes place at Barham Crematorium today at 2pm.

The infamous security robbers stole £53million from a depot in Tonbridge

The Securitas robbery took place on the evening of February 21 when a gang of men abducted and threatened the family of the depot's manager, who lived in Herne Bay.

Fourteen staff at the depot in Vale Road, Tonbridge, were tied up and held in cages while the robbers removed £53,116,760, which belonged to the Bank of England.

Police arrested a number of people over the next 12 months and in June 2007 a trial began at the Old Bailey.

Six months later, the jury returned guilty verdicts on five of the robbers. They received sentences of at least 10 years.

Two other men were cleared of all charges while another suspect is believed to have fled to West Indies with a substantial amount of money.

The mastermind of the heist was martial arts expert Lee Murray, 35, who had escaped to Morocco where he was arrested. He was jailed for 25 years and must spend the first 10 in Morocco before he is returned to the UK.

Police have recovered £21million of the stolen money.