OUISTREHAM, France (AP) - The captain of the giant Royal Navy battleship called his officers together to give them a first morsel of one of World War II´s most closely guarded secrets: Prepare yourselves, he said, for "an extremely important task."

"Speculations abound," one of the officers wrote in his diary that day - June 2, 1944. "Some say a second front, some say we are to escort the Soviets, or doing something else around Iceland. No one is allowed ashore."

The secret was D-Day - the June 6, 1944, invasion of Nazi-occupied France with the world´s largest-ever sea, land and air armada. It punctured Adolf Hitler´s fearsome "Atlantic Wall" defenses and sped the dictator´s downfall 11 months later.

The diary writer was Lam Ping-yu - a Chinese officer who crossed the world with two dozen comrades-in-arms from China to train and serve with Allied forces in Europe.

For 32-year-old Lam, watching the landings in Normandy, France, unfold from aboard the battleship HMS Ramillies proved to be momentous.

His meticulously detailed but long-forgotten diary was rescued by urban explorers from a Hong Kong tenement block which was about to be demolished. It is bringing his story back to life and shedding light on the participation of Chinese officers in the multinational invasion.

Sau Ying Lam poses with a photo of her father Lam Ping-yu on the beach in Ouistreham, France, on Saturday Oct. 4, 2025. (AP Photo/John Leicester)

As survivors of the Battle of Normandy disappear, Lam´s compelling firsthand account adds another vivid voice to the huge library of recollections that the World War II generation is leaving behind, ensuring that its sacrifices for freedom and the international cooperation that defeated Nazism aren´t forgotten.

"Saw the army´s landing craft, as numerous as ants, scattered and wriggling all over the sea, moving southward," Lam wrote on the evening of June 5, as the invasion fleet steamed across the English Channel.

"Everyone at action stations. We should be able to reach our designated location around 4-5 a.m. tomorrow and initiate bombardment of the French coast," he wrote.

Sleuthing by history enthusiasts Angus Hui and John Mak in Hong Kong pieced together the story of how Lam found himself aboard HMS Ramillies and proved vital in verifying the authenticity of his 80-page diary, written in 13,000 wispy, delicate Chinese characters.

Hui and Mak have curated and are touring an exhibition about Lam, his diary and the other Chinese officers - now on display in the Normandy town of Ouistreham.

One breakthrough was their discovery, confirmed in Hong Kong land records, that the abandoned 9th-floor flat where the diary was found had belonged to one of Lam´s brothers.

Another was Hui´s unearthing in British archives of a 1944 ship´s log from HMS Ramillies. A May 29 entry recorded that two Chinese officers had come aboard. Misspelling Lam´s surname, it reads: "Junior Lieut Le Ping Yu Chinese Navy joined ship."

Lam´s leather-bound black notebook has had a dramatic life, too.

Lost and then found, it has now gone missing again. Hui and Mak say it appears to have been squirreled away somewhere - possibly taken to the U.S. or the U.K. by people who emigrated from Hong Kong - after the explorers riffled through the apartment, salvaging the diary, other papers, a suitcase, and other curios, before the building was demolished.

But Hui, who lived close by, got to photograph the diary´s pages before it disappeared, preserving Lam´s account.

"I knew, 'Okay, this is a fascinating story that we need to know more about,´" he says.

"Such a remarkable piece of history ... could have remained buried forever," Mak says.

They shared Lam´s account with his daughter, Sau Ying Lam, who lives in Pittsburgh. She previously knew very little about her father´s wartime experiences. He died in 2000.

"I was flabbergasted," she says. "It´s a gift of me learning who he was as a young person and understanding him better now, because I didn´t have that opportunity when he was still alive."

Lam was part of a group of more than 20 Chinese naval officers sent during World War II for training in the U.K. by Chiang Kai-shek. Chiang led a Nationalist government in China from 1928 to 1949, fighting invasion by Japan and then Mao Zedong´s communists, before fleeing to Taiwan with the remnants of his forces when Mao´s insurgents took power.

On their long journey from China, the officers passed through Egypt - a photo shows them posing in front of the pyramids in their white uniforms - before joining up with British forces.

In his diary, Lam wrote of a narrow brush with death on D-Day aboard HMS Ramillies, as the battleship´s mighty guns were pounding German fortifications with massive 880-kilogram (1,938-pound) shells before Allied troops hit the five invasion beaches.

"Three torpedoes were fired at us," Lam wrote. "We managed to dodge them."

His daughter marvels at the lucky escape.

"If that torpedo had hit the ship, I wouldn´t be alive," she says.

Through ships´ logs, Hui and Mak say they´ve confirmed that at least 14 Chinese officers participated in Operation Neptune, the naval component of the invasion which was code-named Operation Overlord. Some 7,000 vessels took part. The Chinese were deployed in pairs, on seven ships, Hui and Mak say.

Some of the officers, including Lam, also saw action in the Allied invasion of southern France that followed, in August 1944.

"Action stations at 4 a.m., traces of the moon still visible, although the horizon is unusually dark," Lam wrote on Aug. 15. "Bombardment of the French coast started at 6, Ramillies didn´t open fire until 7.

"The Germans put up such a feeble resistance, one can call it nonexistent."

France awarded its highest honor, the Légion d´honneur, to the Chinese contingent´s last survivor in 2006. Huang Tingxin, then 88, dedicated the award to all those who traveled with him from China to Europe, saying "it was a great honor to join the anti-Nazi war," China´s official Xinhua News Agency reported at the time.

Lam´s daughter says their story remains inspirational.

"It talks about unity, talks about hard work, about doing good," she says. "World War II, I think it shows us that we can work together for common good."

___

Leung reported from Hong Kong.

An exhibit on display shows members of a Chinese contingent of naval officers who travelled to Europe in World War II to train with British forces, including Lam Ping-yu, who kept a diary and is shown by a blue arrow, in Ouistreham, France, Oct. 4, 2025. (AP Photo/John Leicester)

This handout photo provided by Huang Shansong, son of Huang Tingxin, one of the 24 officers sent to Britain, Chinese naval officers pose for a photo in front of a pyramid on Sept. 8, 1943, in Egypt during their journey to Britain for training. (Huang Shansong via AP)

A suitcase recovered from an abandoned Hong Kong apartment, where a World War II diary written by Chinese naval officer Lam Ping-yu was also found, is exhibited in Ouistreham, France, Oct. 4, 2025 . (AP Photo/John Leicester)

FILE - This photograph is believed to show E Company, 16th Regiment, 1st Infantry Division, participating in the first wave of assaults during D-Day in Normandy, France, June 6, 1944. (Chief Photographer's Mate Robert M. Sargent, U.S. Coast Guard via AP, File)

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