In April 1949, the HMS Amethyst was en route on the Yangtze River from Shanghai to Nanking China to replace another ship guarding the British Embassy during the Civil War between the Nationalist and Communist Chinese.
Early in he morning, the Amethyst received a burst of small arms fire and a salvo of shells from a People’s Liberation Army (PLA) gun battery on the bank of the river. The PLA claimed the artillery shells, most of which fell short of the ship, were intended for Nationalist forces on the opposite bank. The Amethyst unfurled Union Jacks and increased speed. There was no further firing from this battery.
Further up river, the ship came under sustained fire from a second PLA battery. By the time the shelling stopped, 22 men had been killed and 31 wounded and the ship had received multiple hits.
Over the next few days, repeated attempts to rescue the Amethyst by British warships were repelled by heavy shore battery fire.
The Amethyst was held captive for almost three months. Ultimately, for release of the ship, the PLA demanded that Britain, the United States, and France withdraw their armed forces from all parts of China. Negotiations broke down.
In July, the Amethyst slipped away in the night and successfully escaped 100 miles downriver on a route lined with hostile guns on both banks of the river.