Draft:Capture of the Upnor

The capture of the Upnor was an incident that occurred on 29 March 1922. The Upnor was hijacked by anti-Treaty Irish Republican Army forces while transporting munitions from Haulbowline in Ireland to Devonport in England.

Shortly after 2pm, an IRA boarding party set out from Cobh aboard the commandeered tugboat Warrior. At dusk, approximately 30 to 40 miles off the Irish coast, the Warrior intercepted the Upnor, which was traveling slowly while towing a barge and had been left behind by two armed trawler escorts. The IRA crew signalled the Upnor to stop under the pretext of delivering an urgent official message. Upon boarding, IRA forces led by Mick Murphy held the captain at gunpoint with a Lewis gun and ordered him below deck. Control of the vessel was transferred to John Duhig, an experienced seaman and IRA member, and as the Warrior steered toward Ballycotton the captured Upnor followed behind. The escorting British trawlers continued ahead, oblivious to the vessel's seizure.

The Upnor was directed to Ballycotton Bay, arriving at the pier around 4am on 30 March. Around 100 people began unloading the cargo into around 100 commandeered lorries. On 3 April 1922, Winston Churchill, then Secretary of State for the Colonies, when answering questions about the capture in the British parliament claimed the cargo consisted of around 400 rifles, 700 revolvers, 39 machine guns, 500,000 rounds of rifle ammunition, and other navel stores, including spare parts and a small quantity of explosives. Unloading took until about 6pm.

Upon learning of the capture after the Upnor's escort reported loss of contact, British naval authorities dispatched a warship from Cobh. By the time it arrived at Ballycotton Bay, the IRA had already dispersed following reports of its imminent arrival, leaving local residents looting the remaining non-military contents of the stranded vessel, and the barge towed by the Upnor, which contained an assortment of office furniture.

Although contemporary British assessments noted that the Upnor’s armoury was not of the highest overall quality, its capture significantly reinforced anti-Treaty IRA forces in the South and contributed directly to an increased reliance on mines in subsequent military engagements.