The privateers, including Captain Robert Searle, arrived at Old Panama City on 27 January 1671; they camped overnight before attacking the following day. They were opposed by approximately 1,200 Spanish infantry and 400 cavalry; most were inexperienced. Morgan sent a 300-strong party of men down a ravine that led to the foot of a small hill on the Spanish right flank. As they disappeared from view, the Spanish front line thought the privateers were retreating, and the left wing broke rank and chased, followed by the remainder of the defending infantry. They were met with well-organised firing from Morgan's main force of troops. When the party came into view at the end of the ravine, they were charged by the Spanish cavalry, but organised fire destroyed the cavalry and the party attacked the flank of the main Spanish force. In an effort to disorganise Morgan's forces, the governor of Panama released two herds of oxen and bulls onto the battlefield; scared by the noise of the gunfire, they turned and stampeded over their keepers and some of the remaining Spanish troops. The battle was a rout: the Spanish lost between 400 and 500 men, against 15 privateers killed.