6 July 2012 Last updated at 12:01 ET

Detained killers of Wahab Zaaki remain silent on motive

Abubakar Alawi and Kai Shannon's actions were called "brutal and cowardly"

Two killers have been detained for life at the Old Bailey after turning down the chance to explain their actions in return for a small sentence reduction.

Kai Shannon and Abubakar Alawi, both 20, killed Wahab Zaaki in 2009 in Walthamstow, east London.

Judge John Bevan had offered a sentence reduction if they told the victim's family why they had killed him.

When they refused he jailed Shannon for 18 years for murder. Alawi was detained for nine years for manslaughter.

Both men had also been found guilty of unlawful wounding.

Mr Zaaki died in the Atlee Terrace Estate during a spate of violence in the capital.

It is thought Mr Zaaki may have been in a dispute over money

The court heard he may have been in dispute with a local gang over just £5.

Mr Zaaki was attacked as he smoked cannabis. A friend who tried to help him was stabbed in the hand.

Judge Bevan called the killing "brutal and cowardly".

He went on: "The use and carrying of knives is a weakness not a strength.

"The message must go out that knife crime is cowardly, morally bereft and socially intolerable."

Judge Bevan had said an explanation of the killers' motives would provide a "small consolation" to Mr Zaaki's family.

But Shannon and Alawi still insisted they did not know, as they were sentenced.

Police said a "ring of fear" had delayed the killers being brought to justice.

The judge awarded £500 to a 20-year-old woman who was a crucial witness in the case.