For 62 years Akira Makino spoke not a word of what he had done. But to those who knew him well it must have been obvious that he was a man with a tortured conscience. Why else would he have returned so often to the obscure, mosquito-blown town in the southern Philippines where he experienced such misery during the Second World War? He set up war memorials, gave clothes to poor children, and bought an entire set of uniforms for a local baseball team.

Last year, at the age of 83, he embarked on a gruelling pilgrimage to 88 Buddhist temples in Japan. After number 40 he collapsed from heat exhaustion, having permanently injured his knees. “My wife didn’t like me going back to the Philippines — she called me ‘war crazy’,” said Mr Makino, a frail old man who lives alone in Hirakata, near Osaka. “But she let me go anyway. Right up until she died three years ago, I never told her. But over time I think she realised.”

Only in the twilight of his life has Mr Makino begun to talk about the secret he carried for more than 60 years. In 1944, as a medical auxiliary in the Imperial Navy, he was stationed on the island of Mindanao in the southern Philippines. There he was party to one of the most notorious and poorly chronicled cruelties of the Japanese war effort — the medical dissection of living prisoners of war.

Over four months before the defeat of the Japanese forces in March 1945, Mr Makino cut open ten Filipino prisoners, including two teenage girls. He amputated their limbs and cut up and removed their livers, kidneys, wombs and still beating hearts for no better reason than to improve his knowledge of anatomy.

“It was educational,” he said. “Even today when I go to see doctors they are impressed by my knowledge of the human body. But if I’m really honest, the reason we did it was to take revenge on these people who were spying for the Americans. Now, of course I feel terrible about the cruel thing that I did, and I think of it so often. But at the time what I felt for these people was closer to hatred than to pity.”

There have been other accounts of medical vivisection, most notoriously by Unit 731, a top-secret arm of the Imperial Army which killed thousands of Chinese and Russian prisoners in Manchuria in the name of scientific research. But Mr Makino’s is the first such testimony to have emerged from the Philippines — and from the Navy, which was regarded as the less cruel and fanatical of the Imperial Armed Forces.

Apart from the extraordinary climax of his wartime story, Mr Makino comes across as a typical Japanese of his generation — a polite, well-meaning man who lacked the courage and daring that would have been needed to stand up to the Imperial war machine. It was in such an atmosphere that he found himself in Zamboanga, a Muslim town in the far southwest of the Philippines.

The population were the Moro people, an assortment of jungle tribes legendary as ferocious head hunters. The Japanese feared and hated them; as the US forces drew closer they arrested many of them as spies and threw them into a hellish pit where they were left to rot. “I don’t know whether they really were spies or not,” Mr Makino said. “All that was needed was for someone to say that they were. We knew that we’d lost the war. Our psychological state was very strange by then. In those conditions, we could do anything, absolutely anything.” It began with a practice that has been described by a number of former Japanese soldiers — the “testing” of traditional Japanese swords on live prisoners.

One day towards the end of 1944, Mr Makino was summoned by his commanding officer, a navy doctor. “He told me that if anything happened to him I had to take over from him. He told me to come and see a vivisection. The first time it was one prisoner, a middle-aged man. He’d already given up — there was no struggle. He was tied to the bed and anaesthetised with ether, so that he was completely unconscious. The lieutenant showed me what to do. He cut him open, and pointed out, ‘Here’s the liver, here’s the kidneys, here’s the heart’. The heart was still beating, then he cut the heart open and showed me the inside. That was when he died.

“I didn’t want to do it, but it was an order, you see. At that time, if a commander gave you an order it was understood that it was the order of the Emperor, and the Emperor was a god. I had no choice — if I had disobeyed I would have been killed.”

The “operation” took about an hour; when it was over the body was sewn up and thrown into a hole in the earth. Eight more vivisections followed, Mr Makino said. “We removed some of the organs and amputated legs and arms. Two of the victims were women, young women, 18 or 19 years old. I hesitate to say it, but we opened up their wombs to show the younger soldiers. They knew very little about women — it was sex education.

When the Americans landed in March 1945, the Japanese scattered into the jungle. Mr Makino spent seven months living like an animal, alone. When he returned to Japan the feelings of remorse began.

He said: “I was under orders, you see. But I know that I did a terrible thing.”

Atrocities remembered

— Up to 300,000 Chinese were killed by biological weapons between 1938 and 1945

— 200,000 women are thought to have been made to work in Japanese military brothels during the war

— The construction of the Railway of Death, linking Thailand and Burma and including the bridge over the River Kwai, cost the lives of 13,000 prisoners of war and up to 100,000 civilians Between December 1937 and March 1938 Japanese troops occupying the Chinese city of Nanjing killed an estimated 275,000 people, many of them women and children

— In 2000 a Japanese company paid $4.6 million compensation to 1,000 foreign labourers forced to work as slaves to support Japan's war effort

Sources: Times archive; the Hoover Institute

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