A retrial had already taken place in 2008.

Prabu said the first thing he did after walking free from court was have a drink with his legal team, who had fought for his release since 2003.

In his first interview since being released, the Mitcham resident - who was facing a life sentence with a minimum term of 16 years - said: "We are over the moon, on top of the world... the family waited a long time for this day.

"In a way I'm angry - but in a way we're glad the right thing has been done. I've heard of people doing a lot more time than us - at least we get half a chance to put things straight and get on with our lives."

He said prison had been a daunting experience, and not the soft touch the public believed.

The 29-year-old said: "At the moment I'm just enjoying the freedom."

He said the brothers, who live in Commonside East, would be considering whether to take legal action against the Government for false imprisonment.

He claimed the group would have been freed before Christmas, but said a hearing eventually held this month, but first scheduled for December, was postponed due to bad weather.

Prabu Santharatnam and Nimalan Nadarajah, 30, of no fixed address, had been found guilty of murder and perverting the course of justice.

Jathies Santharatnam and Mayuran Seevaratnam, 29, of no fixed address, were convicted of manslaughter.

Jathies was also convicted of perverting the course of justice.

But the group's convictions were overturned at the Court of Appeal on Tuesday, 12 April, after new witness evidence - which Mr Santharatnam could not discuss as it is the subject of possible legal action - emerged.

A fifth man, 30-year-old Nimalrajah Thambithurai, of Tooting, also had a conviction of conspiracy to assault Mr Balasingham quashed.

During the 2003 trial a jury was told Mr Balasingham had been fatally wounded in a grassy area in between Kent Close and Huntington Close on the Pollards Hill Estate on 6 November, 2001.

It heard the 36-year-old, a production manager at the Sunlight Laundry in Deer Park Road, Wimbledon, was returning from work to his home in Huntington Close when he suffered the injuries at about 11pm.

He was taken to Mayday Hospital in Croydon and declared. dead shortly after midnight on 7 November.