For 62 years, Akira Makino spoke not a word of what he’d 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 had experience 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 frailold 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 which he had carried.

In 1944, as a medical auxiliary in the Japanese Imperial Navy, he was stationed in 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 and murder of living prisoners of war.

Over the course of four months before the defeat of the Japanese forces in March 1945, Mr Makino cut open the bodies of ten Filipino prisoners, including two teenage girls. He amputated their limbs, and cut up and removed their healthy 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 typical of Japanese of his generation - a polite, well meaning man who lacked the immense courage and daring which would have been needed to stand up to the Imperial war machine. He was born in 1922 and grew in the port city of Kobe, where he joined the Navy in 1940. After training as a medical corpsman, he found himself sailing to and fro across East Asia in the mighty Yamato, the biggest battleship ever created. By 1942, though, the Imperial forces were on the defensive and even to sailors such as Mr Makino, defeat seemed inevitable.

“New soldiers started arriving, and they were younger and younger, 15 or 16 years old,” he remembers. “We said, ’Where are you guns?’, and they replied, ’We have no guns - but we have bamboo spears.’ It was then I knew that we had already lost the war.” It was in such an atmosphere that he found himself in Zamboanga, a Muslim town in the far south-west of the Philippines.

The local population were the Moro people, an assortment of jungle tribes legendary as ferocious head hunters. The occupying 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,” said Mr Makino. “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 which has been described by a number of former Japanese soldiers - the “testing” of traditional Japanese swords on live prisoners. “There were university graduates who had no idea how to fight, but who were officers because of their education,” Mr Makino says. “They carried swords, but never used them. They’d say, ’Bring the POWs - we will see how sharp these swords are!’ So they tied up the prisoners and chopped their heads off. But the swords were so rusty, they couldn’t do it cleanly.”

One day towards the end of 1944, Mr Makino was summoned by his commanding officer, a navy doctor whom, even now, he declines to name. “I was his number two, and 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, up to three hours long. “Over the course of time, I got used to it,” he 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.

“I admired the lieutenant, and I was flattered that he asked me to do this because he really trusted me. I felt truly honoured. But now I know I was used.” When the Americans landed in force in March 1945, the Japanese scattered into the jungle. Mr Makino spent seven months there, until well after the Japanese surrender, living like an animal off cats, snakes, lizards and licking water off leaves, utterly alone. A photograph take of him after his rescue by locals shows a living skeleton. But as soon as he had returned to Japan, the feelings of remorse began.

He married, had two sons, worked in a hospital and became a salaryman for a construction company. And whenever he could he returned to Zamboanga. He published a pamphlet about his experiences and spoke in schools about the horrors of war. But he never spoke of the experiments, until October when he was being interviewed by a Japanese newspaper. “It slipped out,” he said. “But now I have talked about it, I must not stop.” Apart from a few local papers, a second interview on the news agency, Kyodo, was largely ignored by the Japanese media, an indication perhaps of the reluctance to air the subject of wartime atrocities. “No one else who knew about it survived, and it is a miracle that I am alive,” said Mr Makino. “I have to talk about it, to tell the story to children who know nothing about such things. It brings me peace to a certain extent, but not a complete peace. I was under orders, you see. But I know that I did a terrible thing.”

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