The campaign comes in the wake of statistics showing that gun warfare among gangs has claimed 24 lives each year in 2001 and 2002, and that 11 people have died already this year.
Posters will show photographs of happy families ripped to pieces, with the line "Don't let guns and drugs R.I.P. your family apart". It advertises a freephone number to encourage people to report gun crime, promising that the call will not be taped or traced and that information can be given anonymously.
The campaign is being run on behalf of Operation Trident, set up by the Metropolitan Police to deal with gun crime in London. It will target the five London boroughs where gun crime is most prevalent: Brent, Hackney, Harringay, Lambeth and Southwark.
Operation Trident officers have already investigated more than 100 different shootings this year, and the campaign aims to humanise these statistics, and show that for every gun-related death, there is a family that is ripped apart.
Commander Cressida Dick, the head of the Met's Operation Trident, said: "Every time there is a shooting at least one family is affected. This means that many peoples' lives, especially those of the victim's family, are changed forever."
R&B artists including Big Bruvas and Javine have also contributed to a public relations campaign, appearing on Kiss 100 to appeal for witness to come forward.
The posters will appear on the streets and in hairdressers. They were created by The Advertising Syndicate, which has worked for the Metropolitan Police for several years.
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