Gardaí are renewing their appeal for information about the murder of Dean Johnston in Dublin, more than four and a half years ago.

The 21-year-old was shot dead as he sat in the back of a friend's car in the Moorefield estate in Clondalkin, just 100 yards from his own home, on the evening of May 25th 2011.

So far nine people have been arrested in relation to the investigation, but nobody has been charged.

Gardai say they have explored 500 lines of inquiry, taken 400 statements and have more than 300 exhibits relating to the case.

Superintendent Dermot Mann from Lucan Garda Station is urging a number of unidentified people who were present on the night to come forward:

Spokesperson for Crimestoppers Cian Connaughton is appealing for anyone with information on Dean Johnston's death to come forward: