A British court has convicted two men of the 1993 murder of black teenager Stephen Lawrence, a landmark case that prompted accusations of "institutional racism" among the London police force.

Gary Dobson, 36, and David Norris, 35, both white men, were found guilty on Tuesday after three days of jury deliberations and a six-week trial that hinged on new scientific evidence presented by prosecutors.

The two men are scheduled for sentencing on Wednesday.

Lawrence was an 18-year-old school student when he was stabbed to death at a bus stop in southeast London in an unprovoked attack by a gang of five white young men who shouted racist epithets.

Lawrence's mother, Doreen, and father, Neville, wept as the verdicts were delivered at the Old Bailey, London's central criminal court, the Press Association reported.

Duwayne Brooks, Lawrence's best friend who had been with him on the night of the murder but managed to escape the gang, tweeted after the verdict: "Some justice at last".

'Huge regret'

The trial of Dobson and Norris, which began in November 2011, hinged on new forensic evidence linking the two men to the murdered teenager.

Prosecutors said textile fibres, blood and hair belonging to Lawrence had been found on clothing seized from the defendants.

The defence argued that the clothes were contaminated during the police investigation because officers did not store them properly.

Dobson pleaded innocent of the crime as he was led from court on Tuesday, however, saying: "You have condemned an innocent man here, I hope you can live with yourselves."

Senior officers from Scotland Yard said they would continue working to find the other members of the gang that attacked Lawrence.

"We do, of course, acknowledge that there were five people involved on the night that Stephen was murdered," said Acting Deputy Commissioner Cressida Dick of London's Metropolitan Police.

"We have not brought all those people to justice. So if we get new evidence, if we have further opportunities, we will respond to that... We don't see this as the end of the road."

She added that it was a "matter of huge regret" that it had taken 18 years to convict anyone for the murder, but insisted the police had changed.

"We've transformed the way we do investigate homicide and I like to think that where we are now exemplifies how we've changed in terms of the way we investigate," she said.

The case became a catalyst for change after London's Metropolitan Police mishandled the initial investigation into Lawrence's death.

'Institutional racism'

A 1999 report by senior judge William Macpherson said the murder had exposed "institutional racism" in the force and also accused officers of incompetence and a failure of leadership.

The impact of the Macpherson inquiry was felt across the public sector, with all bodies being required to put in place policies to prevent and address racism.

The Lawrence case also helped end the judicial doctrine of double jeopardy, which had previously prevented suspects from being tried twice for the same crime.

One of the defendants, Dobson, had been acquitted of the murder in 1996 when a private prosecution, brought by the teenager's parents, fell apart.

The Court of Appeal quashed that acquittal in May 2011 and said Dobson could stand trial again, a decision made possible after double jeopardy was scrapped in 2005.

Source: Al Jazeera and agencies