The bombardment from the sea, supplemented by fire from some guns which had been landed from "Pomona", continued on the night of 19 October, occupying the garrison which did not notice storming parties of seamen, marines and soldiers infiltrating the fort. The surprise was complete and there were only six British casualties. The treasure found in the fort and on board two treasure ships was worth some two million dollars. Two hundred and fifty quintals of mercury were also found in the fort. The fort itself was abandoned by the British at the end of November, before a Spanish counterattack arrived. The craters from the British bombardment are still visible in the walls of the fort today.