Scotland Yard is asking for information to identity the man in a photograph who could have been the first black police officer in the Metropolitan force.
The photograph is dated 3 September 1910 and was taken at an event celebrating the first local fire engine at Prickend Pond, Chislehurst, Kent.
As part of preparations for Black History Month, the Black Police Association's 10th anniversary and its 175th anniversary, the Met is keen to discover his identity.
Commander Steve Allen, head of the Met's diversity directorate, said the image provides "a glimpse of our history". Mr Allen said: "He must have been one of the first black police officers in the Met and must have found an environment very different to that of today. He was one of the pioneers in being a black role model in the capital's criminal justice system."
Anyone with information can contact the Black Police Association on 020 7230 2457 or 2447.