Battle of Ty - ho Bay The Battle of Ty - ho Bay was a significant naval engagement in 1855 involving the British Royal Navy , the United States Navy and Chinese pirates . The action off Tai O , Hong Kong was to rescue captured merchant vessels , held by a fleet of armed war - junks . British and American forces defeated the pirates in one of the last major battles between Chinese pirate fleets and western navies . It was also one of the first joint operations undertaken by British and American forces . Background . Unlike the Atlantic Ocean where piracy was largely over by 1830 , piracy in Asia and elsewhere in the Pacific continued to thrive as it had for centuries . Chinese and Japan ese pirates constantly fought each other along China ' s coastal regions , thus hundreds of pirate hideouts existed all over the Chinese coast by 1855 . This prompted western naval forces to fight them when they attacked shipping . Sometime in September 1855 , the pirates of Kuhlan seized four merchant vessels in that area which were under escort by the paddle steamer HMS " Eaglet " . In response the Royal Navy sloop - of - war HMS " Rattler " was sent to rescue the merchantmen . HMS " Rattler " found the pirates in Kuhlan Harbor but shallow water prevented her from attacking so she left to seek aid from the " Eaglet " and USS " Powhatan " . " Powhatan " , was a screw frigate of the East India Squadron and commanded by Commodore William J . McCluney . " Rattler " was commanded by Commodore William Fellowes and was manned by 180 officers and crew . The number of crew and armament of " Eaglet " is unknown but she was originally a civil vessel chartered for British naval service between 1855 and 1857 , to tow British vessels through shallow water . Battle . On August 4 , the steamer " Eaglet " arrived at Ty - ho Bay , she was towing at least six boats of different types , filled with British and American sailors and marines . Each boat was armed with a howitzer or cannon . The British first spotted a merchant junk which appeared to be fleeing the bay so the pinnace of the " Rattler " and the cutter of the " Powhatan " were sent to cut the junk out . Minutes later , when the pinnace and cutter disappeared from sight , the remaining British and American vessels sighted the pirate fleet which included fourteen large junks and twenty - two smaller ones . Some 1 , 500 pirates crewed the vessels and they were armed with small cannons . Also in the bay were seven captured merchant ships , most of which were Chinese junks . When the Chinese sighted the approaching enemy half of the pirate junks began to flee while the other remained behind to engage . The pirates began a heavy fire on the British and Americans but most of the shot was not well directed and passed over the " Eaglet " and the armed boats . When the expedition was in range the boats started their return fire and six junks were sunk at this time . When the range decreased to close quarters , " Eaglet " detached the boats and they went off to board the junks . Fourteen were taken with heavy resistance and were burned just after . The seven merchant ships were also liberated but two were heavily damaged in the battle and subsequently burned as well . As result of the action , fourteen larger junks were destroyed along with six small ones while sixteen others escaped . An estimated 500 pirates were killed in action , drowned , or were wounded . Around 1 , 000 pirates were taken prisoner . American casualties consisted of six wounded with five dead out of about 100 men , the dead were crewmen John Pepper , James A . Halsey , Isaac Coe , Landsman , S . Mullard and B . F . Addamson . The British suffered several wounded and four men killed , officer George Mitchell , and crewmen James Silvers , John Massey , and M . Oliff . The battle is largely forgotten but a monument was erected at Happy Valley in commemoration , it was later moved to the city of Hong Kong .