PC Keith Blakelock died during riots on the Broadwater Farm estate in Tottenham, north London, on 6 October 1985.
Twenty-eight years later, a new suspect - 44-year-old Nicholas Jacobs - has been charged with the officer's murder.
- PC Blakelock, 40, was stabbed to death as he tried to protect firefighters tackling a blaze at a supermarket at the height of the unrest
- Three men - Winston Silcott, Mark Braithwaite and Engin Raghip - were convicted in March 1987 of Blakelock's murder
- All three convictions were quashed four and a half years later, after forensic tests on pages of key interview records suggested they had been fabricated
- Scotland Yard reopened the murder investigation in 2003 after a review indicated there were possible new lines of inquiry
- In 2010, 14 men were arrested in connection with PC Blakelock's death and the attempted murder of his colleague PC Richard Coombes
- Nine were told in August 2011 that they would face no further action, and the rest except Jacobs have now been released.
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