The PSNI said today they believe they have identified the "Real IRA" bomb team that killed a workman at a territorial army base a year ago.
But even though eight suspects have been questioned, detectives have been unable to get enough evidence to press charges.
Construction worker Mr David Caldwell (51) died when he picked up a booby-trapped lunchbox which exploded in his hands.
Detective Inspector Robbie Paul said the PSNI were close to charging the killers who struck at the base in Derry on August 1st, 2002.
The gang used wire cutters to break through a perimeter fence of the base on the Limavady Road in the city and abandoned the bomb.
Inspector Paul said he believed that Mr Caldwell was not the specific target but that the device was left for the first person who picked it up and it could have killed any of the mixed workforce.