New testimonies from survivors and recently examined military archives suggest that French chemical weapons Algeria operations were systematically used during the Algerian War of Independence, particularly in cave networks where fighters and civilians sought refuge. The revelations shed light on a controversial chapter of the conflict that remained largely hidden for decades.
Amar Aun was just 15 years old in 1959 when French forces attacked the Ushhatu cave in eastern Algeria. He and dozens of villagers had taken shelter there after fleeing bombardment and gunfire. According to his account, helicopters arrived and released thick black smoke into the cave.
“We inhaled it and began coughing,” he recalled. “Green drool appeared at the corners of our mouths, and people fell one after another.”
Another survivor, Muhammad Labachi, was 12 at the time. He described scenes of chaos as the gas spread through the cave. People shouted, cried, and struggled to breathe as visibility disappeared. His uncle, who suffered from asthma, suffocated inside the cavern.
The attack in March 1959 reportedly killed more than a hundred people, many of them civilians who had sought refuge alongside members of the National Liberation Army.
Historians now say such incidents were not isolated. Documents uncovered in French military archives suggest the use of chemical agents was authorized during the conflict that began in 1954, when Algeria’s National Liberation Front launched a campaign to end more than a century of French colonial rule.
A letter dated May 1956 shows senior military authorities discussing the “use of chemicals” in Algeria. Subsequent reports outline experiments with gases intended to flush fighters out of caves, which had become key hideouts and logistical bases for guerrilla units operating in mountainous regions.
These operations eventually led to the creation of specialized “special weapons platoons.” Their task was to locate caves suspected of sheltering rebels and deploy chemical agents to force occupants to surrender or neutralize them.
Former French soldiers have described these missions in personal diaries and testimonies. One veteran said his unit’s instructions were simple: search the cave, deploy gas, and if possible destroy the entrance afterward to prevent further use.
The chemicals reportedly included a mixture known as CN2D, combining chloroacetophenone and arsenic-based compounds. Military experts say the mixture could cause severe respiratory distress, vomiting, burning lungs, and eventual suffocation if exposure continued.
French soldiers themselves were sometimes exposed during operations. Some veterans later reported chronic respiratory illnesses and struggled for decades to obtain recognition from authorities that their health problems were linked to chemical exposure during the war.
Research by historian Christophe Lafaye suggests the scale of these operations may have been far greater than previously believed. By examining declassified files and soldiers’ personal records, he estimates that thousands of gas attacks may have been carried out across Algeria’s mountainous regions.
So far, Lafaye has identified only a few hundred documented incidents, indicating that the full extent of the campaign remains unknown.
The use of such weapons appears to have contradicted international agreements already in place at the time. The 1925 Geneva Protocol banned chemical and biological weapons in warfare, although many countries continued to maintain stockpiles and programs during the Cold War era.
Despite the evidence emerging from archives and testimonies, the issue remains politically sensitive. Many official documents remain classified, and French authorities have rarely commented publicly on the allegations.
For survivors and families of victims, however, the memories remain vivid. In the village near the Ushhatu cave, a memorial honors the victims of the 1959 attack. Local residents say the tragedy affected nearly every household in the area.
More than six decades after the war ended with Algeria’s independence in 1962, historians argue that acknowledging the events is essential for understanding the full history of the conflict and its lasting impact on both nations.
Sami B. is the founder and editor of Algeria News Gate, an independent English-language platform covering Algeria’s political, economic, and business developments. Based in Europe, he reports on official announcements, economic trends, and international relations involving Algeria.