The Chinese were defeated in the only military confrontation, but the Portuguese called off further punitive measures after a naval explosion killed about 200 sailors.

The Portuguese governor João Maria Ferreira do Amaral had adopted a confrontational stance towards the Chinese, as displayed in the earlier revolt of the faitiões (October 1846).

Further, he ordered Chinese residents within the walls to pay taxes to the Portuguese authorities and no longer to the imperial mandarins.

[2] Amaral also placed stricter controls on the lorcha traffic and tried to stop the mandarins from collecting customary dues from the Tanka people who lived on boats in the harbour, since Macau was a free port.

[2] The two were only a few hundred yards within the gate when a Chinese coolie frightened Amaral's horse with a bamboo pole and signalled to his comrades in hiding.

Intending to collect the reward in Guangzhou, the assassins cut off Amaral's head and remaining hand as proof.

The USS Plymouth and Dolphin took up defensive positions in the harbour, while HMS Amazon and Medea landed some Royal Marines to defend Portuguese civilians and British nationals.

On 25 August, the guns of the imperial fort of Latashi (拉塔石), known to the Portuguese as Passaleão,[5] about one mile north of the city, opened fire on the walls of Macau.

In this situation, Vicente Nicolau de Mesquita, an artillery sub-lieutenant, volunteered to lead an attack on Baishaling with a company of about thirty-six men and a howitzer.

[2] To calm the Portuguese, Xu Guangjin, Viceroy of Liangguang, ordered the arrest of Shen Zhiliang, the lead conspirator.