The bomb was triggered via command wire leading to a hill overlooking the scene. Between 300-400lbs of explosive had been packed into two milk churns and stuffed into the culvert.
All three of the victims belonged to the 1st Battalion Royal Scots Regiment and came from villages in Midlothian. Pte David Ferguson was 20 and came from the village of Stoneyburn. He was survived by his wife and child. Pte Roderick Bannon was 25 and came from the village of Kirknewton. He was also married and had a nine-month-old son. Pte John Pearson was 23, single, and from the village of Newtongrange.
Their commanding officer paid tribute to the men, but said their deaths would not deter the army from protecting the community from sectarian attacks. Lt Col Philip Davies said these were the regiment's first deaths in Northern Ireland and also the first soldiers to be killed by the IRA's South Armagh Brigade since the end of an IRA ceasefire two months earlier. He added that the attack may have been in direct response to the sentencing of a South Armagh terrorist jailed in Belfast over the murders of four soldiers in July 1975.