Footage of an attack in which a man was fatally stabbed has been released in a bid to track down his killer.
Aqib Mazhar was killed when the car he was in was stopped and attacked in Nottingham in June 2016.
While five others have been jailed over his death, the man holding the knife has not been found, despite a £10,000 reward for information.
Detectives hope the footage of the "horrific" killing will prompt witnesses to come forward.
CCTV shows the car stopped on Russell Road after it was "boxed in" by three other vehicles.
A group of men with bars and knives can be seen swarming around the car.
One, in a black hood, runs to a rear door and pulls it open, before leaning inside and stabbing Mr Mazhar.
Four men, from Nottingham and Derby, were jailed after they all pleaded guilty to manslaughter.
Another man, who was 18 at the time, was also jailed for manslaughter in May 2017.
At the beginning of May, Mr Mazhar's mother, Shameem Akhtar, made a plea for information, saying the killing had made every day since "agony".
Last week charity Crimestoppers offered a £10,000 reward for information which led to the killer.
City Ch Insp Donna Lawton said: "This horrific incident highlights the devastating impact that knife crime can have on families and their communities and we really hope that someone comes forward as a result of this appeal.
"Carrying a knife is completely unacceptable and our knife crime team along with every other police officer will keep targeting this issue, removing any weapons they come across and proactively arresting those who possess one."