David Croke left prison only weeks before the murder of Mr Raja. With his violent past, his name featured early on as a suspect.

Croke's blood sample was found on the door of Mr Raja's home in July 1999.

But it was not until Suffolk Police arrested him on a minor drugs charge two years later that his DNA was tested.

His previous crimes took place before the national DNA database was established.

When his DNA was compared with the blood smear at the scene, there was a one-in-a-billion chance it came from someone else. Police arrested him in Brighton in February last year.

Father-of-two Croke had been sentenced to 23 years behind bars in 1988 for his part in a series of armed robberies around London.

He and his accomplices stole more than £1 million in the raids, in which security guards were threatened with guns and strapped with fake bombs.

The robberies dated back to 1984. In one, a security van was raided and a driver bound and gagged. Croke and his accomplices made off with £250,000.

In September 1985, Croke and two others entered a security depot, threatened staff with a gun, bound and gagged them and strapped a mock bomb to one of the victims.

In December 1985, with two others, he entered a security guard's home, threatened his wife and children, strapped a fake bomb to the guard and then took him to a depot where they stole £480,000.

In August 1986, with an accomplice, Croke followed a security van on the M1. They stole £283,000 but were later caught by police.

When he was jailed at the Old Bailey, ten similar charges were ordered to lie on file. Croke appealed against his sentence and, in April 1990, it was reduced to 20 years.

His jail term ended more than a decade where bookish Croke, one of five children growing up near in Edmonton, London, lived the high life on the proceeds of crime.

He flew all over the world, spending time in Hong Kong and the Mediterranean, and bought a villa in Malta where he would entertain friends and associates.

Penniless after his release, he came to stay with his sister Rosie, 62, in a flat in Bolney Road, Moulsecoomb, Brighton.

His belongings amounted to a bag of clothes, some letters and a few photos from the old days.

Rosie said: "He was in such a bad state. He was as thin as a rake.

"He was too scared to go outside. He'd just sit and watch TV and every day I'd go and pick up a copy of the Daily Mail for him.

"We had a homecoming party for him, just his close family, but he didn't like it. He couldn't stand being around too many people.

"He'd got into drugs while he was in prison and after he was let out I invited him to stay with me so he could clean himself up. He didn't touch a thing while he was down here, just a sleeping pill at night."

Croke left prison in May 1999, just weeks before the murder of Mr Raja.

He worked briefly at a halfway house, delivering packages in the London area. His defence team suggested his blood might have been found on Mr Raja's front door frame because he made a delivery there.

The team said he was painting his son's house in Enfield on the day of the killing.

He was living with wife Rita at the time, also in Enfield, but split with her soon after, sleeping on a couch in the lounge of Rosie's maisonette.

She said: "He was just living on the dole, eating, smoking and sleeping. We did have a laugh in the evenings, though. About once a month he'd drive up to London - he told me he was visiting his sons."

Croke had been on remand since his arrest.

Rosie said: "He said it's not worth my bothering to go and see him in prison. I keep in touch by writing and on the phone."