(also known as the Battle of the Pagoda Anchorage) on 23 August 1884, the French took their revenge for the Bắc Lệ Ambush. In a two-hour engagement watched with professional interest by neutral British and American vessels (the battle was one of the first occasions on which the spar torpedo was successfully deployed), Courbet's Far East Squadron annihilated China's outclassed Fujian fleet and severely damaged the Foochow Navy Yard (which, ironically, had been built under the direction of the French administrator Prosper Giquel). Nine Chinese ships were sunk in less than an hour, including the corvette Yangwu, the flagship of the Fujian fleet. Chinese losses may have amounted to 3,000 dead, while French losses were minimal. Courbet then successfully withdrew down the Min River to the open sea, destroying several Chinese shore batteries from behind as he took the French squadron through the Min'an and Jinpai passes. Riots in Hong Kong The French attack at Fuzhou effectively ended diplomatic contacts between France and China. Although neither country declared war, the dispute would now be settled on the battlefield. The news of the destruction of the Fujian fleet was greeted by an outbreak of patriotic fervour in China, marred by attacks on foreigners and foreign property. There was considerable sympathy for China in Europe, and the Chinese were able to hire a number of British, German and American army and navy officers as advisers. Patriotic indignation spread to the British colony of Hong Kong. In September 1884 dock workers in Hong Kong refused to repair the French ironclad La Galissonnière, which had suffered shell damage in the August naval engagements. The strike collapsed at the end of September, but the dock workers were prevented from resuming their business by other groups of Chinese workers, including longshoremen, sedan chair carriers and rickshawmen. An attempt by the British authorities to protect the dock workers against harassment resulted in serious rioting on 3 October, during which at least one rioter was shot dead and several Sikh constables were injured. The British suspected, with good reason, that the disturbances had been fomented by the Chinese authorities in Guangdong province. French occupation of Keelung Meanwhile, the French decided to put pressure on China by landing an expeditionary corps in northern Formosa to seize Keelung and Tamsui, redeeming the failure of 6 August and finally winning the 'pledge' they sought. On 1 October Lieutenant-Colonel Bertaux-Levillain landed at