Detectives are appealing directly to the borough’s Algerian community to help solve a case involving the murder of a police officer 20 years ago.

Jim Morrisson, 26, was fatally stabbed in Westminster in December 1991 trying to arrest a man for a bag theft while off duty.

Police believe the Algerian community may be able to help them in their hunt for the killer and have released a video appealing for information in Arabic for the first time, as well as making renewed enquiries around the Blackstock Road area of Finsbury Park.

As well as appeals from DC Morrisson’s widow Victoria and investigating officers, the video also features Toufik Kacimi, director of the Muslim Welfare House, Finsbury Park.

He said: “This horrible crime had a terrible impact on our community. The Algerian community has come a long way since the 90s and it is time now to put this horrible crime behind us.

“Please help the police with vital information. We are all responsible. Unless we help the police they will never be able to do their jobs properly.

“If you are not confident in telling the police come to me or speak to your local Imam.”

Detectives from Scotland Yard have also been making direct appeals to the Finsbury Park Algerian businesses and residents.

Senior investigating officer DCI Amanda Hargreaves, Homicide and Serious Crime Command, said: “DC Morrison was a talented young officer with a bright and promising future, which was taken away from him when he was brutally attacked.

“Over the years, officers have remained diligent in attempting to solve this case. Despite the passage of time, I believe there are people who still hold vital information about who is responsible for DC Morrison’s murder.

“Allegiances and loyalties can change in the intervening years and I appeal directly to those individuals with information to get in contact.”

A �20,000 reward is on offer for information leading to the arrest and prosecution of the person responsible.

DC Morrison’s widow, Victoria, said: “I was 24-years-old and in the first few years of marriage. I was suddenly widowed and my whole life was turned upside down. It has been very traumatic for me and for Jim’s family. Even 20 years on, it is still very, very hard.”

At the time of the attack on December 13, in Montreal Place, the suspect was described as being of Algerian or North African origin, 5ft 10 inches tall, aged approx 27 to 30. He was medium build, clean shaven, with dark collar length hair which had distinctive tight curls at the front, and wore a brown leather jacket.

Anyone with information should call the incident room on 020 8721 4155, email operationeffner@met.police.uk or call Crimestoppers anonymously on 0800 555 111.