On the night of 16 October 1976 the Gardaí received an anonymous telephone call stating that Provisional IRA members were at a vacant farm at Garryhinch, near Portarlington, County Laois, engaged in activity connected with a plot to target a local Fine GaelTD and Parliamentary Secretary to the Minister of Defence, Oliver J. Flanagan. Clerkin with four fellow Gardaí were dispatched from Portarlington Garda Station to investigate the report. However, the telephone call was bogus and was from the IRA itself, aimed at luring Garda officers to the farmhouse as a part of a planned ambush by the organization against the Irish Government in retaliation for its institution of the 'Emergency Powers Act', which passed into Irish Statute that same night, aimed at combating escalating paramilitary activity in the Republic of Ireland associated with the IRA's armed campaign. Arriving at the farmhouse the Garda team found it apparently unoccupied, with no one in the vicinity and its front door locked. Clerkin entered the premises via an open rear window, and moving through the building finding it to be apparently deserted, opened the front door from within to admit his colleagues. The door was booby-trapped with a bomb, housed in a large used propane gas cylinder which had been dug into the ground beneath the floorboards of the farmhouse's entrance doorway, which was triggered and detonated upon the door being opened, killing Clerkin standing directly above instantly. On the building's outside all the other Garda team were also caught in the blast, Detective Peters being permanently blinded and deafened, and Gardas Cannon, Thornton, and Bohan also being wounded, the quantity of explosive utilized being of sufficient power to demolish the building. Clerkin was in his 25th year.
Aftermath
The remains of Clerkin's shattered body were buried at Latlurcan Cemetery in his hometown of Monaghan. Although there were a number of arrests by the Garda in an intensive search across the Laois-Offaly district for the perpetrators of the ambush, which resulted in a signed confession from a prime suspect, no one has ever been convicted or brought to trial for it. The survivors of the attack received the Liddy Medal from the Garda Síochána Retired Members Association, awarded for bravery in the line of duty to retired Gardaí officers. A memorial mass for Clerkin on the 40th anniversary of the attack was held in Portarlington on 16 October 2016. Michael Clerkin was awarded the Garda's Scott Medal posthumously on 8 December 2017 in a ceremony at the Garda Training College at Templemore. A memorial plaque was erected to his memory in his home town of Monaghan in June 2018.
