The final siege started in August 1645 when Colonel John Dalbier, with 800 troops, took up position around the walls. The garrison held out, despite further reinforcements to the attacking force, until Oliver Cromwell arrived with a heavy siege-train. By 14 October 1645, the New House had been taken and the defences of the Old House breached. The final storming took place across the link from the New House. Many valuable goods were carried off, and a fire destroyed the building, as well as killing several priests who had taken refuge in the cellar. From the first firing of the guns, the assault was over in forty-five minutes, with the fires raging for up to nine hours after the event.