1945年日本投降之際，臭名昭著的「731部隊」為掩蓋其長達十多年在中國所犯下的細菌戰與活體實驗罪行，決定在撤退前對關押在實驗室內的中國人進行大規模屠殺，企圖毀滅一切證據。然而，在這場血腥的清洗行動中，奇蹟般有四名中國抗日戰士死裡逃生，成為萬餘名受害者中極少數的倖存者。

731部隊的首腦石井四郎雖然身為醫學博士，卻殘酷無情。他深知若實驗行為曝光，將可能使日本及其本人遭受法律制裁，因此對所有被關押的受害者下達嚴密監管的命令，不容許任何人有逃脫的機會。然而，儘管管理嚴苛，依然有四位抗日志士從魔窟中生還，他們分別是國民黨吉林第三督導區108支部書記李廣德、黨員何家訓、110支部書記張人天，以及抗聯的中共偵察員李遇遲。

這四人當時被囚禁在佳木斯市的一個731分隊實驗室，長期遭受非人道虐待與慘烈的活體實驗折磨。1945年8月12日夜，隨著蘇聯紅軍節節勝利，即將攻入牡丹江，731部隊決定對所有囚犯進行屠殺以滅口。石井四郎將此任務交給特務橋本喜一郎等五人，他們按照計畫對囚犯連續進行多輪射擊。由於受害者已連續兩天兩夜未進食，體力極度虛弱，日本人原以為無人能逃過此劫。

然而，四人卻以不同方式僥倖倖存。張人天憑藉過往的軍事經驗，聽見日軍上膛聲後，立即閃入牢房死角，在敵人換彈夾的空隙，迅速躲入一具中槍身亡的同伴屍體下。雖被流彈擊中手臂，但傷勢不算嚴重，成為傷勢最輕的倖存者。何家訓在首輪射擊時亦躲在死角，不料隨後仍被擊中兩槍，倒地掙扎。日軍為徹底斃命，朝其頭部開槍，子彈貫穿雙頰並打掉四顆牙齒，鮮血噴湧，他瞬間昏迷不動。日本人誤以為他已死，未再補槍。實際上，他僅受重傷，反倒奇蹟生還。

至於李廣德與李遇遲，境遇更加險惡。二人平日審問時態度強硬，令日軍恨之入骨，於是遭集火射擊，雙雙身中八槍。李廣德左腿被齊膝打斷，李遇遲胸部中彈兩次，照理難以倖免，但兩人竟在鮮血中硬是活了下來。

屠殺後，日本人並未入內逐一確認生死。由於蘇聯紅軍已逼近，他們匆忙將牢房潑滿汽油點燃後便倉促撤離。也正是這樣的疏忽，讓這四名抗日志士僥倖逃脫死亡，成為迄今為止已知的731部隊極少數倖存者。他們的經歷不僅揭露日本軍國主義的殘暴罪行，更成為後世審視歷史、追求公義的重要見證。

In 1945, following Japan’s surrender, the notorious “Unit 731” attempted to destroy evidence of its more than a decade of atrocities in China, which included biological warfare and human experimentation. Before retreating, the unit carried out a mass execution of the Chinese prisoners held in its laboratories. Amid this bloodbath, four Chinese resistance fighters miraculously survived, becoming the only known survivors among tens of thousands of victims.

The head of Unit 731, Shiro Ishii, though a medical doctor, was ruthless. He feared that news of the experiments on living humans would eventually bring legal consequences to Japan and to himself. For this reason, he ordered that all prisoners be strictly guarded, leaving no chance of escape. Despite these measures, four men managed to survive: Li Guangde, secretary of the 108th Branch of the Kuomintang’s Third Supervisory District of Jilin; party member He Jiaxun; Zhang Rentian, secretary of the 110th Branch; and Li Yuchi, a Communist reconnaissance agent of the Northeast Anti-Japanese United Army.

The four were imprisoned in a Unit 731 detachment laboratory in the city of Jiamusi, where they suffered inhumane abuse and were subjected to horrific live experiments. On the night of August 12, 1945, as Soviet forces advanced rapidly toward Mudanjiang, Unit 731 resolved to massacre all detainees to cover up their crimes. Ishii assigned the task to five agents led by Kiichiro Hashimoto. According to plan, the prisoners were subjected to multiple rounds of gunfire. Weakened after going two days without food, almost no one was expected to survive.

Yet the four men each found their own path to survival. Zhang Rentian, with his military experience, reacted instantly upon hearing the Japanese soldiers load their rifles. He darted into a corner of the cell and, during the momentary pause when the attackers reloaded, hid beneath the body of a comrade who had already been killed. Though a stray bullet struck his arm, the rest hit the body shielding him, leaving him the least injured of the four. He Jiaxun also avoided the first volley by hiding in a blind spot, but was later hit twice and collapsed in pain. To ensure his death, the Japanese aimed for his head, and a bullet pierced through both cheeks, knocking out four teeth. He fell unconscious in a pool of blood, motionless, leading the soldiers to believe he was dead. In reality, he was gravely wounded but still alive.

Li Guangde and Li Yuchi fared even worse. Known for their defiance during interrogations, they were despised by the Japanese, who emptied entire clips into them. Both were struck eight times; Li Guangde’s left leg was shattered at the knee, while Li Yuchi was hit twice in the chest. Incredibly, both men clung to life despite their devastating injuries.

After the massacre, the Japanese did not reenter the cell to check for survivors. With the Soviet Red Army closing in, they hastily doused the site with gasoline, set it aflame, and fled. This oversight allowed the four fighters to survive the inferno.

These men remain the only known survivors of Unit 731’s atrocities. Their survival not only exposed the brutality of Japanese militarism but also serves as vital testimony for history and the pursuit of justice.