Declassified state papers reveal that the Irish government complained to British ministers in 1991 about the alleged harassment of vessels in Carlingford Lough by a Royal Marines patrol boat. The issue was raised by Declan O'Donovan of the Anglo-Irish Secretariat at a meeting on 31 October 1991, highlighting the need for sensitivity by British search parties.
A memo from the Northern Ireland Office, dated 15 November 1991, outlined the 'line to take' for then Secretary of State Peter Brooke at the Anglo-Irish Conference. It expressed hope that 'patrolling designed to deny terrorists use of the lough should not become the source of political friction' and that confrontations with yachtsmen should be minimised, while noting the lough provided 'a very real potential opportunity for terrorists'.
The memo detailed an incident on 21 October 1991, when the crew of the yacht Gurlough complained to the Irish government. They alleged that a Royal Marines boarding party searched their vessel in Irish territorial waters, pointed weapons at them despite no hostility, claimed British ownership of the entire lough, and deliberately drenched the crew.
A British report by the Senior Naval Officer Northern Ireland stated that the Marines warned the crew they would be taken to Warrenpoint, County Down, if they did not cooperate, where the RUC would take over. It acknowledged that weapons were likely 'unintentionally pointed' at the crew but denied any aggression. The Marines also refuted the drenching claim, citing adverse weather conditions. The report concluded the boarding was conducted in 'a professional, courteous and correct manner'.
