The Cnocán Mór Ambush occurred on 27 June 1921 on the Milltown-Tuam road. A flying column of seven local volunteers under the command of Tom Dunleavy, lay in wait for a combined RIC and Black and Tan patrol. Two members of the patrol were killed, Sergeant James Murrin and Constable Edgar Day, while a policeman was wounded and a Black and Tan named Carter escaped. Sergeant Murrin was to have retired on a pension a week earlier but due to a problem with his final documentation, he was required to remain at his post. Constable Day was a young man from Nottingham.