 All were killed in separate incidents except for two of the RUC officers, who were shot by IRA gunmen after a car chase.One of the officers, Kenneth Sheehan, had just returned to duty after being seriously injured in an ambush in Derry in 1976.In April 1978, a plaque was dedicated at his former school, Portora Royal School in Enniskillen, to commemorate his death and that of two other former pupils and RUC men killed in the Troubles.