British anti-terror agents tracked an alleged Irish Republican Army dissident by planting an electronic surveillance device on his car, a prosecutor said Monday at the start of the trial of two men charged with murdering a policeman.
Both men deny fatally shooting Constable Stephen Carroll in a March 2009 ambush claimed by the Continuity IRA splinter group.
Carroll, 48, was the first policeman to be killed in Northern Ireland since 1998, the year of the Good Friday peace accord that sought to end decades of bloodshed over the British territory. While most IRA members disarmed and renounced violence in 2005, small breakaway groups continue to mount sporadic gun and bomb attacks.
The evidence to be presented in coming weeks against alleged IRA dissidents Brendan McConville, 40, and John Wootton, 20, should throw a spotlight on how anti-terror authorities led by the British domestic spy agency MI5 operate in Northern Ireland today.
State prosecutor Ciaran Murphy told Belfast Crown Court that police could connect both defendants to the killing partly because agents planted a GPS tracking device on Wootton's car weeks before the gun attack.
Murphy said agents and detectives would testify that Wootton's car was at the scene of the killing and left it minutes after the officer was shot through the back of the head as he sat in his patrol car in the town of Craigavon.
The policeman's killers lured him to his death by throwing a brick through a window of a family's home and waiting for police to respond. Murphy said Carroll was shot by a Kalashnikov assault rifle from about 50 meters (yards) away.
The attack came two days after another splinter faction, the Real IRA, shot to death two off-duty British soldiers as they collected pizzas from deliverymen at the entrance of an army base in nearby Antrim.
Murphy said police used the GPS data to locate Wootton's car and found inside it a coat belonging to McConville, a former politician from the Irish nationalist Sinn Fein party. He said forensic experts found traces of gunshot residue and Semtex plastic explosive on the jacket.
He said officers found the Kalashnikov hidden under an oil tank outside a Craigavon house.
Libya supplied several tons of Semtex to the IRA in the mid-1980s. Most of the IRA's remaining stock was surrendered to disarmament officials in 2005 but dissidents seized some, too.
IRA dissidents have used Semtex in several attacks since 2008, usually as the core explosive in a larger homemade bomb.