On 14 April 1922, a group of 200 anti-Treaty IRA men occupied the Four Courts in Dublin in defiance of the Provisional government. Collins, who wanted to avoid civil war at all costs, did not attack them until June 1922, when British pressure also forced his hand. After a final attempt to persuade the men to leave, Collins borrowed two 18 pounder artillery pieces from the British and bombarded the Four Courts until the men surrendered.