Unhealed Wounds: Human Experimentation at Shinagawa POW Hospital

by Sapphire Dingler

Shinagawa’s story begins under its original name, Shinagawa POW Camp, officially established on September 12, 1942, in Shinagawa-ku, within the Keihin Unga Kensetsu office. Just thirteen days later, it was reorganized and renamed the Tokyo POW Main Camp (Omori). The entire compound was relocated to a man-made island in Ōmori-ku, Iriarai-machi, a year later, and was largely built by prisoners from Shinagawa Camp. By August 1 of 1943, the Japanese military carved out Shinagawa Hospital, a separate facility ostensibly to treat malnourished and diseased captives.

Despite its outward appearance as just another POW camp, Shinagawa Hospital quickly became the site of clandestine experimentation under the supervision of Captain Hisakichi Tokuda, who served as its senior Japanese medical officer and commandant. In a postwar deposition used at Tokuda’s Yokohama Class B/C War Crimes Trial, Lt./Cmdr. J.R. Davis (USN) described Tokuda’s behavior and appearance:
“Tokuda is repulsive in his appearance. He is slender, about five feet in height, slightly stooped, and very bow-legged. His weight may be about 100 pounds. His vision is bad, and at Shinagawa he wore heavy spectacles without which he was helpless. … He was quite studious, and he would spend hours and hours, day after day, in his room with piles of books all about him. When a shipment of books from the International YMCA came for Christmas of 1944 and again in 1945, he appropriated the very excellent medical books included therein and kept them for his own use.” 
Tokuda (nicknamed the “Spider” and “Dung in Britches” by the POWs for the way that he walked) oversaw “soy-bean milk” injection experiments, initially administered as a purported nutritional supplement but resulting in multiple deaths, and repeatedly falsified postmortem diagnosis to hide the true cause of death of his victims. These actions eventually led to his conviction (Case Docket No. 186) and death sentence (later commuted) for war crimes.

Staffing and Infrastructure

Shinagawa Hospital POW camp from above: https://2nd4thmgb.com.au/camp/shinagawa-hospital-honshu-japan/

Geographically, the hospital was located north of Tokyo Bay, approximately two miles southeast of Ōfuna Camp and adjacent to civilian neighborhoods that included small factories and worker housing. Its position allowed for the rapid transport of ailing prisoners via rail and barge, while still maintaining relative isolation from dense urban centers.
Strategically, the Japanese military selected Shinagawa as its hospital because it offered immediate access to Tokyo’s medical schools and supply chains. Tokyo’s role as a command hub meant that medical orders, personnel, and supplies could flow directly to Shinagawa Hospital without needing to pass through more remote, understaffed camps. Isolating POWs on a separate island helped conceal both routine medical care and the clandestine experiments later conducted under Captain Hisakichi Tokuda.
Though Shinagawa Hospital’s medical affiliations and uniformed nurses suggested a standard military infirmary, its wards were chronically overcrowded and understocked. Eyewitness accounts describe rows of wooden cots crammed side by side (sometimes with two or three men per cot) as influenza, dysentery, and tuberculosis swept through. Food shortages meant patients often subsisted on meager rice porridge, with protein supplements—ostensibly “fellow prisoners prepared soy‐bean milk,” which Allied medical POWs reported for oral consumption, yet each day a cup was set aside for injection experiments rather than for legitimate nutrition. Sanitation was dire: running water was intermittent, latrine facilities overflowed, and vermin were common in ward corridors.
Despite occasional visits by Japanese nurses in spotless uniforms, Allied doctors, when allowed to inspect, found that the storerooms were nearly bare of antibiotics, analgesics, or even basic bandages. In his diary, Weinstein (Allied POW medical aid who, after the war, went on to write a memoir of his time in war) describes having to scavenge leftover dressings from amputations to treat infected wounds, all while witnessing Japanese surgeons perform vivisections on incapacitated men. 
Shinagawa Hospital was organized into multiple wards, each intended to hold roughly fifty to seventy patients, though the exact official capacity figures vary by source. Japanese medical personnel oversaw all clinical operations, headed by Captain Hisakichi Tokuda, the senior medical officer prosecuted in Yokohama’s Class B/C Trials. Tokuda was supported by a small staff of Japanese surgeons, nurses, and orderlies drawn from nearby Tokyo medical schools, alongside noncommissioned medical assistants from the Imperial Japanese Army. Allied medical staff were assigned to “assist” the Japanese doctors, but were mostly relegated to menial duties, such as dressing wounds and translating. Lyon’s (Allied POW witness used by prosecution against Tokuda) papers note that while Japanese doctors performed routine examinations, Allied medical officers were often asked to demonstrate basic procedures (e.g., dressing change techniques) under Japanese supervision, but were barred from prescribing treatments or independently diagnosing serious illnesses. In their testimonies, the Allied medical POWs noted that the skills of Tokuda were lackluster at best, and a deadly hazard at worst.
“[POWs] were operated on at night while [Tokuda] was out of camp. This was done in the face of his direct orders forbidding any surgery being done other than by Dr. Tokuda. Black with anger the next morning, he cussed and howled when he found out that a victim - had escaped his tender ministration. We told him blandly that it was an emergency and we were unable to reach him. These operations were done on the wards, kneeling on the straw-covered floor.” - Alfred A. Weinstein, M.D. POW Allied doctor and prisoner at Shinagawa. 
Admission to Shinagawa Hospital came primarily from POW compounds located in Tokyo (Ōfuna Camp and the surrounding Omori complex) via barge or rail. When a prisoner developed severe malnutrition, tuberculosis, or wounds, camp guards ordered their transfer. At Omori docks, inmates were loaded onto hospital barges under Japanese guard and taken directly to the island facility. Once admitted, prisoners were registered under Japanese‐assigned identification numbers, which Tokuda’s staff used to manipulate case records when falsifying causes of death.
According to transcripts from the Yokohama Class B/C War Crimes Trials, former POW nurse’s aide John H. Williamson provided key testimony against Captain Hisakichi Tokuda, recalling his experiences at Shinagawa Hospital in harrowing detail. Trained in both general and field ambulance procedures, Williamson was assigned as a medical assistant under Tokuda, where he routinely observed and participated in camp medical operations, many of which he later revealed, were deeply unethical.
In his testimony, Williamson described how Tokuda routinely instructed him to set aside a daily cup of soybean milk, a nutrient-dense food supplement made on-site by fellow prisoners. While soybean milk was generally used to combat malnutrition when consumed orally, Tokuda selected it as his injectable substance of choice. He believed its high protein content might yield physiological results when injected directly, despite its unsuitability for intravenous use. Crucially, Tokuda did not strain the milk, and Williamson noted that large clumps were often present in the mixture. These unfiltered injections left swollen welts at the administration sites—swellings so severe that Williamson and others had to massage the areas in hopes of reducing pain and tissue damage.
The first known subject of these injections was a British POW named Holland, admitted to Shinagawa near the end of 1944. Initially diagnosed with nonspecific stomach ailments—diagnoses which shifted multiple times before arriving at “stomach cancer”—Holland was administered the first experimental soybean milk injection. He died shortly afterward, suffering violent convulsions and foaming at the mouth in what eyewitnesses described as an agonizing death.
Testimony from the trials identified several additional victims of Tokuda’s unauthorized procedures. These included Thomas Hampson (injection), Ernesto Saxida (injection, three times—once in the jugular), Raymond Lease (unauthorized surgery), Clifford W. Fusselman (induced lung collapse), and Walter Dawson (injection). Each were subjected to experimental treatments without informed consent, in violation of both wartime medical ethics and international law.

Of these cases, the death of Italian POW Ernesto Saxida stands out for its severity. According to Specification 3 in the docket, “The witness, Williamson, testified that Saxida was admitted to ward No. 5 in March 1945. The diagnosis was cirrhosis of the liver. He further stated: ‘We used to take Saxida to the operating theater about three time a week as he was filling up with water very fast. The accused used to carry on the process of taking the water from his stomach. He didn’t show any signs of improvement and also he was getting vitamin B and soy bean milk everyday (R95). In June, Saxida, – first of all, I was called to the office by the accused and given a cup of soy bean milk to take it down to the operating theater and this I did, and then I went back to the accused who told me to bring Saxida back to the operating theater. He went over and sat in the chair and the needle was stuck in the stomach attached to which was a tuber running down between his legs. While the fluid was running, sometimes for three hours, the accused was busy boiling the soy bean milk. I didn’t know what he was going to use it for and he told me to hold the cup and he took a syringe with about 20cc’s and filled it. He told me to cotton-swab him and then he injected him with the soy bean milk and we didn’t know what the results would be. Saxida was then taken to ward that day and around about 4 or 5 o’clock before supper, I was called in and Saxida’s bowels had collapsed and the feces was running away from him and his legs were going as though he were on a bicycle, also he was foaming at the mouth. I lifted up his eye lids and his pupils were dilated. I sent for Dr. Tokuda and told him what happened and there is a Japanese word, ‘kashini’, I think it means ‘I do not understand’, but that is all I got out of him. No medication was given for him. I stayed with him that night and he seemed to pull around, ​towards 3 o’clock, he said something in Italian, I couldn’t make out what said and I put my hands in front of his face to draw attention, but he was still staring and his pupils were dilated’. ‘The next day, he seemed to ‘pull around’. He acted like a baby, very childish. Three days after the first injection, he was given another injection of soy bean milk.’ He told Dr. Keschner about it (R97). The witness continued: ‘I took him back to the ward, fully expecting what was to come – that is, I had already seen it previously. He let out a scream – I thought he wasn’t going to have any reaction, then he let out a scream; his legs started working again; his arms; he was frothing at the mouth; he was kicking around so much that we had to place him down to the tatami, otherwise, he would have injured himself. He carried on about 18 hours in this condition before he came out of it again. He still wasn’t rational.’Saxida received his first injection on 26 June 1945. He received his second injection on the 29th of June 1945. “After the second injection the accused sent for me on the morning of the 30th and he asked him ‘how’s Saxida’. I told him that Saxida was very ill and that he was unconscious. In the afternoon of the same day, I was sent for to the laboratory(R98). When I got there, I was told to prepare soy bean milk. It was all on the fire and the sterilizer boiled it. The accused again filled the syringe with 20 cc’s of soy bean milk. I didn’t know who it was for – we went to the first room and he told me to prepare Saxida for another injection. Saxida was unconscious. He tried to give intravenous injection in his arm. It was impossible on account of the condition of edema, the swelling in the area. He said, ‘Okay, jugular..’ The patient came to and started howling – after six attempts to get the jugular vein, he finally got it. He shoved the 20 cc’s of soy bean milk in the man’s neck. After he took away the needle, there was a large lump, in that form, on the neck where the soy bean milk had been injected. He told me to massage it; I didn’t know what effects that would have on him. That afternoon, I had to stay with him and see what came out of it. He lapsed unconscious again and died. This was on the 30th of June in the afternoon. He lapsed unconscious until 2 o’clock in the morning of the 1st of July and I saw that he wasn’t breathing. I went over to check and found that the patient had died.’ The accused did not strain or filter the soy bean milk which he injected (R99). Nor could it have been filtered by someone else(R100).”

Saxida survived the first injection but exhibited signs of neurological trauma—violent convulsions, foaming at the mouth, and a marked cognitive decline suggestive of brain damage. Two more injections followed, with the final one delivered into his jugular vein after earlier injection sites had swollen beyond use. He lost consciousness shortly afterward and died within hours. Tokuda’s signed death certificate recorded the cause as “cirrhosis of the liver,” concealing the experimental nature of his treatment.
War Crimes Trials and Documentation:
Following Japan’s surrender, Captain Hisakichi Tokuda was tried in the Yokohama Class B/C Tribunals. In Case Docket No. 186, the panel found Tokuda guilty of conducting lethal “soy‐bean milk” injections on malnourished POWs at Shinagawa Hospital; he was originally sentenced to death, although that sentence was later commuted and he was released circa 1958. The National Archives’ collection of trial exhibits includes Tokuda’s testimony and the medical records he falsified, demonstrating the tribunal’s reliance on Japanese‐language documents and Allied witness depositions. Colonel Henry Lyon’s postwar reports—filed under the U.S. Army’s Judge Advocate General’s office—reference Shinagawa explicitly, describing how Japanese personnel systematically altered death certificates to hide experimental deaths, and noting that surviving POWs provided crucial firsthand accounts.
Historical Significance and Legacy
Today, the former site of Omori (Shinagawa) POW Camp is marked by the Heiwajima Kannon memorial, featuring a statue of Kannon (the goddess of mercy) and a Japanese signboard that offers only euphemistic references to the camp’s history, while most of the grounds have been redeveloped into condominiums and residential buildings. As a cautionary tale, Shinagawa continues to resonate: warning medical professionals of the perils of unaccountable authority, reminding historians of the importance of survivor testimony, and challenging the public to confront uncomfortable truths.
Readers are encouraged to explore PAE’s online resources, review Lyon’s reports, and share local archives to keep Shinagawa’s legacy alive.
Works Cited
POW Research Network Japan. “POW Camps in Japan Proper (Shinagawa Entry).” Accessed June 5, 2025. http://www.powresearch.jp/en/archive/camplist/index.html#tokyo.
U.S. National Archives. Select Documents on Japanese War Crimes and Japanese Biological Warfare. Accessed June 5, 2025. https://www.archives.gov/files/iwg/japanese-war-crimes/select-documents.pdf.
Stanford University Libraries, Virtual Tribunals. “Reviews of Yokohama Class B and Class C War Crimes Trials: Case Docket Number 186, Hisakichi Tokuda.” Accessed June 5, 2025. https://exhibits.stanford.edu/virtual-tribunals/catalog/mg979yc6070.
Roland, Charles G. Long Night’s Journey into Day: Prisoners of War in Hong Kong and Japan, 1941–1945. Toronto: John P. McGovern Foundation, 1996.
Colonel Henry Lyon’s War Crimes Papers, University of Tennessee Libraries, accessed June 5, 2025, https://scout.lib.utk.edu/subjects/522.
“The Hazards of a Japanese ‘Infirmary,’” WWII Today, April 12, 2024, https://www.ww2today.com/p/44-04-12-the-hazards-of-a-japanese-infirmary.