THE date is April 20, 1949 and China is in the middle of a bloody civil war.

The Communist People's Liberation Army led by Mao Tse Tung and the nationalist Kuomintang are at each other's throats on the banks of the river Yangtze during China's War of Liberation.

Four years previously Great Britain, the USA and the Soviet Union all agreed a policy of non-intervention in Chinese domestic affairs under the Moscow Declaration.

As the Chinese Civil War raged on, the Communists began to make headway on the shores of the Yangtze River, near the city of Nanking and warned that any foreign ships in the river would be attacked.

The UK Government had a ship stay in China as a guard ship to protect British embassy staff in Nanking. The HMS Amethyst, under diplomatic anchorage, was sailing up the Yangtze River to Nanking to relieve the HMS Consort of her guard ship duty when all of a sudden communist Chinese batteries started firing heavily upon the ship, killing 22 of the crew - including the captain.

The ship ran aground at the nearby Rose island and was severely damaged. Over 50 of the crew were either killed, dying or seriously injured. Some were evacuated to Shanghai and were treated in hospital. The ship was subsequently stuck on the Yangtze River for over 100 days before making a miraculous escape to the opening of the South China Sea on July 30 1949.

Prior to this there were three other ships involved in assisted escape attempts; the destroyer HMS Consort, the frigate HMS Black Swan and the cruiser HMS London. All three suffered heavy damage and casualties in their attempts to save the Amethyst.

Due to the narrowness of the Yangtze River none of the ships were able to manoeuvre and were effectively sitting ducks for the communist field guns.

When the HMS Amethyst made her daring escape on July 30, 1949, the HMS Concord entered the Chinese territorial waters of the Yangtze to escort and cover the Amethyst past the massive guns of the Woosung Forts - the last obstacle before reaching the South China Sea.

The HMS Concord's Quartermaster Able Seaman Taff Dixon has been ordered to deliver instructions by word-of-mouth - not over the tannoy, as sound piping sound would carry over water and could alert the enemy - that the ship was to travel up river into Chinese territorial waters.

Sailing at a pace of 20 knots, the Concord was challenged by a Nationalist gunboat near the Tunghsan Banks Buoy and ordered not to travel any further. Stopping until the nationalist ship had left their vicinity, the Concord then sailed past the heavily armed Woosung Forts - more than forty miles into Chinese territorial waters - under a dense fog later that night and meet the Amethyst meeting it four miles past the Woosung Fort.

"Fancy meeting you here," a Concord crew member said in a transmission to the Amethyst.

"Never, repeat never has a ship been more welcome," replied the Amethyst communications operative.

Having now past the Woosung Forts without them opening fire, the Concord - still in the Yangtze River - transferred supplies and 147 tons of fuel to the Amethyst which had only seven tons of fuel left. As they made it into the neutral waters of the South China Sea, both ships set course for the British province of Hong Kong, expecting  the party of a lifetime.

After the Concord and Amethyst cleared the River Yangtze Sir Ralph Steven, the British Ambassador in Nanking sent a telegram to the British Foreign Office in Singapore stating: "No, repeat, no publicity should be given to the fact that HMS Concord entered Chinese Territorial waters."

This telegram was to prevent an international incident as Cold War tensions were high and it removed any official mention of the Concord's involvement in the Yangtze Incident.

The Concord was soon met by the HMS Cossack and the Cossack's captain boarded the ship. He ordered the Concord to patrol Northern China and removed the ship's log book - taking with him any evidence of the Concord's involvement.