Virtual reality may help solve the murder of policeman Keith Blakelock.

PC Blakelock was working in London when he was killed during the Tottenham riot in 1985.

Officers have fed photographs of the riot scene through a special computer program to plot where witnesses and suspects were at the time the officer was killed.

His widow, Elizabeth Johnson, from West Boldon, South Tyneside, has welcomed the new move which may bring the killers to justice.

Elizabeth Johnson: Welcomed investigation

Sunderland-born PC Blakelock, who was posthumously awarded the Queen's Medal for Bravery, died after confronting rioters who were rampaging through a housing estate in Tottenham, north London.

Three men from London were convicted of murdering PC Blakelock in 1987, but cleared on appeal four years later amid claims the evidence in the case may have been fabricated.

Mrs Johnson said: "Anything that brings Keith's killers to justice has to be a good thing. We'll have to see what happens."

Police in London began a review of PC Blakelock's killing in 1999 after pressure from Mrs Johnson.

The virtual reality reconstruction of the murder scene will allow detectives to picture the Broadwater Farm estate as it was in 1985.

A spokesman for the Metropolitan Police said: "The review team has used computerised software to reconstruct the Broadwater Farm estate so that they can make sense of material under review."