A police watchdog will investigate whether allegations of corruption in the Stephen Lawrence murder investigation were not passed on to a major inquiry.
Scotland Yard said it called in the Independent Police Complaints Commission today after reviewing "a considerable number of files and reports dating back to the 1980s".
The review was sparked amid claims that a confidential report compiled by the force's anti-corruption command was not disclosed to the panel of the 1998 Macpherson inquiry that examined the force's handling of the case.
A force statement said: "The Directorate of Professional Standards has reviewed a considerable number of files and reports dating back to the 1980s as well as conducting interviews with a number of key individuals involved in the original investigation into both Stephen Lawrence's murder and police corruption.
"We have retrieved a number of key documents, which greatly assist in understanding what material was available to the Macpherson inquiry and are now in the process of sharing our findings with the Independent Police Complaints Commission so that they can review it in the light of their previous involvement in the case."
The announcement comes after the teenager's mother, Doreen Lawrence, called for the reopening of the major public inquiry into the circumstances of his death.
Documents were said to focus on the conduct and integrity of former Metropolitan Police commander Ray Adams, who was involved in the probe into the murder.
Despite investigating the claims for more than a month, Scotland Yard has been unable to confirm if the potentially crucial files were passed to the inquiry, headed by Sir William Macpherson.
Home Secretary Theresa May has since offered to meet Mrs Lawrence, who said the claims gave further impetus to her calls for a public inquiry.
Some of the allegations against Mr Adams centred on his relationship with Kenneth Noye, who was later convicted of a separate murder.
No criminal or misconduct charges were brought as a result of the internal investigation into Mr Adams.
He was questioned at the Macpherson inquiry about corruption, but no evidence of wrongdoing was found.
During the Macpherson inquiry, lawyers claimed Noye had a criminal associate, Clifford Norris, whose son David was a prime suspect in the murder of Stephen.
David Norris and Gary Dobson were convicted of Stephen's murder in January this year - 19 years after the crime - and sentenced to life at the Old Bailey.
It has also been claimed that another Scotland Yard officer, who interviewed the suspects following Stephen's killing, had links to Clifford Norris.
Former detective sergeant John Davidson denies any wrongdoing.
The Metropolitan Police statement came as Mrs Lawrence joined a vigil with the family of Trayvon Martin, the unarmed teenager who was shot dead in Florida by a Neighbourhood Watch volunteer.