The Castlerock killings took place on 25 March 1993 in the village of Castlerock, County Londonderry, Northern Ireland. Members of the Ulster Defence Association (UDA), a loyalist paramilitary group, shot dead three civilians and a Provisional Irish Republican Army volunteer as they arrived for work. Another was wounded. The men were all Catholics.
The five men were builders and had been renovating houses in the Gortree Park housing estate for some months. As they arrived in their van at Gortree Park, at least two gunmen jumped out of another van and opened fire. Those killed were James McKenna (52), Gerard Dalrymple (58), Noel O'Kane (20) and Provisional IRA volunteer James Kelly (25).
The gunmen drove off toward Castlerock before doing a U-turn and passing their victims again. The van used by the gunmen was found burnt-out two miles from the attack. Later in the day, the UDA shot dead a Catholic civilian and wounded another at Dairy Farm Shopping Centre in Belfast.
The UDA claimed responsibility for the attack using the covername "Ulster Freedom Fighters" (UFF) and said the men were republicans. Sinn Féin councillor Patsy Groogan said the men were regularly stopped and harassed by the security forces and that he had "no doubt that this behaviour played a part in targeting these men for assassination".
The weapons were later used by the same gang in carrying out the Halloween Greysteel massacre at the Rising Sun pub on 31 October 1993. It has been claimed that one of the gang was a double agent and protected by RUC Special Branch. Torrens Knight received eight life sentences for the Greysteel massacre, together with four more for the Castlerock killings. He served seven years in the Maze Prison before paramilitary prisoners were granted a general release under the Belfast Agreement.