The British warships, whose claimed right of passage, per Treaty of Tientsin, along the Yangtze had been unchallenged previously since the late Qing dynasty, came under bombardment by PLA artillery and were forced to withdraw permanently from Chinese territorial waters.

[11] On 20 April 1949, during the Chinese Civil War between the nationalist Kuomintang-led Republic of China and the Chinese Communist Party, the Royal Navy sloop HMS Amethyst, commanded by Lieutenant Commander Bernard Skinner,[12] was cruising on the river Yangtze from Shanghai to Nanjing,[Note 1] to replace HMS Consort, which had been posted as guard ship for the British Embassy there.

[citation needed] Speed was increased, and large Union flags were unfurled on either side of the ship, after which there was no more firing from this battery.

The coxswain on the wheel, Leading Seaman Leslie Frank, was seriously injured and, as a result, the ship slewed to port and grounded on the river's bank.

[13] PLA shells exploded in the sick bay, the port engine room, and finally the generator, just after the injured Weston's last transmission: "Under heavy fire.

Fifty-nine ratings and four Chinese mess boys made it to the Kuomintang-controlled southern bank, but two men were assumed drowned while swimming ashore.

Rear Admiral Alexander Madden, the second in command of the East Indies Fleet, ordered the destroyer HMS Consort (Commander Robertson) to go from Nanjing, to Amethyst's assistance, and the frigate HMS Black Swan (Captain Jay) to go from Shanghai to Jiangyin, 40 mi (64 km) down river from Amethyst.

The Assistant British Naval Attaché, Lieutenant Commander John Kerans, joined the ship on 22 April, after he had dealt with all the wounded and unwounded men who had been sent ashore.

On 21 April, a signal was received: "HM ships London and Black Swan are moving up river to escort the Amethyst down stream.

The cruiser HMS London, alongside Black Swan, were bombarded intensely as they attempted to help Amethyst, and retreated with 3 killed and 14 wounded.

On 30 April 1949, the Chinese Communists demanded that Britain, the United States, and France quickly withdraw their armed forces from any part of China.

(Eventually, in 1988, the PLA commander Ye Fei, admitted that it was his troops that fired first,[14] thinking it was an American naval intervention.

On 30 July 1949, Amethyst's chain was slipped and the ship headed downriver in the dark, beginning a dash to escape from the Yangtze River by following in the wake of the civilian ship Kiang Ling Liberation, a fully-lit passenger vessel carrying Chinese refugees, allegedly in the hope that the observers ashore would be confused and not see the frigate in the dark, and to follow the path through the shoals taken by Kiang Ling Liberation.

At 05:25 a planned meeting with the destroyer HMS Concord occurred, at which time Amethyst sent the signal "Have rejoined the fleet south of Wusong.

Fortunately for the British, Amethyst was not detected by the shore batteries and the two ships then proceeded downriver until at 07:15 they ended action stations and after passing through the river's outlet arrived at the Saddle Islands at 12:00 hrs to anchor and transfer much needed oil and stores.

[17]Soon after, on 5 August 1949, Lt Cdr Kerans was awarded the Distinguished Service Order for his actions in bringing Amethyst to safety.

After receiving medical care, he recovered and continued to perform his duties catching rats, protecting the dwindling food supply during the 101-day siege and helped boost morale for the surviving sailors.

[citation needed] The American radio series Suspense included an episode entitled "Log of the Marne" (22 October 1951), based largely on the events of the Yangtze incident.