Mae Sot, Thailand – Once again, the attack came from the sky.
The Kachin resistance fighters barely heard the sound of the propellers as the Myanmar military’s two drones released their payload above their heads in northern Kachin State in late April.
“I fell down to the ground when the bombs dropped,” Aung Nge, a fighter with the Kachin People’s Defense Force (PDF), told Al Jazeera from an undisclosed location. “I didn’t lose consciousness. I was awake the whole time.”
The drone attack seriously injured three men who were holed up close to the front line in Kachin State where battles with the armed forces have been escalating since October last year.
In critical condition, field medics sent the men to a hidden hospital deep in the jungle where they could be treated by professional doctors.
Within a day of receiving treatment, however, one of the soldiers started to show symptoms the doctors could not understand and his condition began to deteriorate rapidly.
Another man from the Kachin Independence Army (KIA), who had been injured in a separate drone strike days after the first attack and appeared to be on the mend with no signs of infection, also took a turn for the worse and died in his sleep.
Aung Nge, meanwhile, was about to endure ghastly infections that would spread across his entire body.
Doctors told Al Jazeera that the men experienced rapid onset necrosis, an effect not normally seen in a blast wound. Necrosis causes the deterioration of most or all of the cells in an organ or tissue due to disease or the failure of the blood supply.
While necrosis can be caused by sepsis, which appears rapidly and is usually accompanied by a fever, doctors said they could find no physiological reason for the rapid deterioration in their patients. Toxic substances can also trigger such reactions, they said.
“In close examination of the wounds, they are rapidly necrotising, easily decomposed and not associated with metallic foreign bodies,” Dr Soe Min, the veteran trauma doctor who treated the suspicious cases, told Al Jazeera. He has been treating combat-related cases since January 2022 and has seen and treated hundreds of blast injuries.
These cases were different, he said.
“After two days, all the wounds became blackish in colour with foul-smelling discharge. The whole left arm had bluish discolouration and the radial pulse was faint. So I had to proceed with mid-arm amputation on the third day,” he said of Aung Nge, the fighter who survived.
Banned weapons
Under the Chemical Weapons Convention (CWC), which Myanmar ratified under a previous quasi-civilian government in 2015, the production, storage and use of chemical weapons is banned under international law. Chemical weapons include riot control substances such as tear gas that can irritate or disorientate soldiers on the battlefield, as well as herbicides and toxins that act on the central nervous system.
The Convention on Certain Conventional Weapons (CCW), meanwhile, seeks to limit or ban the use of weapons that might cause soldiers “unnecessary or unjustifiable suffering” or “affect civilians indiscriminately”. Myanmar is not among the 126 states that have ratified or acceded to the convention as of July 1 last year, according to the UN.
Myanmar’s military, which seized power in a coup in February 2021, has previously been accused of using banned weapons – against the Kachin in 2014 and against the Karen, another ethnic armed group, in 2005. Neither case was proved definitively.
The current regime, which calls itself the State Administration Council (SAC), has already been accused of war crimes, including indiscriminate air attacks on civilians and the wholesale burning of villages.
Now, fighters are reporting encounters with potentially noxious weapons. In March, the Pa-O National Liberation Army (PLNA), an ethnic armed group, reported that the military had dropped chemical weapons in Hsi Hseng in southern Shan State during clashes.
The following month, in eastern Karen State’s Kawkareik Township, another resistance group made similar allegations. The “Joker Column”, an armed faction there, alleged that 30 of their fighters experienced symptoms from an attack with what they described as “poison gas bombs”. One of the armed group’s members said their comrades were struggling to breathe and vomiting.
Human rights experts say claims that banned and restricted weapons are being used should be investigated and verified by a credible, independent group.
“It would be quite a major thing if substantial evidence was uncovered, but the evidentiary threshold is, and should be, quite high,” David Scott Mathieson, an independent analyst, told Al Jazeera. “It would then need to go to the CCW committee and what ramifications any breach of the treaty would entail. It would likely [result] in calls for sanctions and possibly suspension as a signatory.”
The Independent Investigative Mechanism for Myanmar (IIMM), a United Nations agency investigating serious crimes and abuses by the military and armed groups, has also been looking into the new claims from the resistance. Although they could not go into details about their research, they told Al Jazeera that they were “aware of certain allegations of chemical weapons use in Myanmar, and are investigating these allegations”.
The Myanmar military did not respond to Al Jazeera’s repeated requests for comment on the allegations.
The National Unity Government (NUG), the parallel government made up of politicians and lawmakers removed by the generals, meanwhile, said they were investigating the claims.
“It’s highly probable that the military uses prohibited weapons to uphold its dominance,” Nay Phone Latt, the spokesperson of the NUG Prime Minister Office, told Al Jazeera. “As a result, the international community needs to keep a close watch on these developments and put pressure on the terrorist military.”
‘We tried to escape’
In April, the Karen National Liberation Army (KNLA) temporarily liberated the key town of Myawaddy on the border with Thailand. In response, the SAC dispatched warplanes to counter the offensive. One local, whose neighbourhood was partially destroyed by air strikes, told Al Jazeera that the subsequent bombings caused him and seven other men to become ill.
Nay Min, 27, told Al Jazeera that the attacks happened so quickly, that his family barely had enough time to pack their things before fleeing.
“We tried to escape but on this day, the air strikes hit at least 80 times near us,” he said. “The scout aeroplane was over my house. And then the house near mine was destroyed by an air strike. And the SAC used the helicopter and started to machine gun the area.”
The sounds of gunfire echoed outside his house. Finally, the family of four with three small children ducked for cover and decided to make a run for it. After they escaped, Nay Min said that he and seven other men briefly went back to their homes to grab some last items before fleeing to Thailand.
Once they entered their neighbourhood, they noticed white smoke drifting in the air, which immediately caused their eyes to burn and made them feel disorientated.
“Suddenly, after we crossed the Moei river to Thailand, three of the men suffered from dizziness and then collapsed,” he said, stressing that it was surprising because the men were particularly well-built and strong.
“One of the three men who fell over was foaming from the mouth. I don’t know what happened to these men or if they survived,” Nay Min said. He added that he experienced burning of the eyes and nonstop tearing for three days afterwards.
‘The more oxygen, the more it burns’
Many resistance groups across the country have made allegations that the SAC is using incendiary weapons, munitions designed to set fire to objects or cause intense burning. They can also cause respiratory injury to people through their chemical reactions. Examples of such weapons include napalm, thermite or white phosphorus, which burns when exposed to air. Rights groups say further investigation would be necessary in order to establish that civilians were being deliberately targeted with such weapons in order to assess whether there had been a violation of international law.
Phoe Thaike Maui, the deputy commander of the Karenni Nationalities Defense Force (KNDF) who is known as Maui, told Al Jazeera in February that he believed the military was sometimes deploying such weapons.
“When these bombs land on the ground, the pieces of the chemical sometimes miss the target or building,” Maui said. “When there’s nothing to burn, it creates this smoke. It reacts with the oxygen and creates white smoke. The more oxygen, then the more it burns.”
“So we’ve seen them using these materials to burn people and also their homes. So the residents don’t want to stay, even in liberated areas.”
The Free Burma Rangers (FBR), a nonprofit organisation offering medical assistance to civilians across Burma’s front lines, also believes the SAC is using incendiary weapons and other noxious chemicals.
Dave Eubank, the group’s founder, is routinely on the front lines.
“I have personally seen incendiary weapons multiple times in Karen State and Karenni State, including one that dropped about 100 metres [328 ft] from us. And those fumes were very noxious, but they’re not deadly directly per se. We’ve also been hit by white phosphorus, not on my body but close to me here in Burma [the former name for Myanmar].”
Free Burma Rangers has also documented the SAC using high-content tear gas on multiple occasions. High-concentration gas can cause more severe health problems than the low-level concentration typically used in crowd-control situations.
“So I know from firsthand experience the Burma military uses incendiary weapons, high content tear gas, and white phosphorus,” Eubank said.
Back in the hidden makeshift clinic in the jungles of Kachin State, Aung Nge lies on a bamboo platform with thick green foliage behind him. A patch of blood is seeping through his bandages as he tries not to move too much. Only a thin layer of tarpaulin shields him from the rain.
“I am feeling better. But I’m still suffering,” he said. “I have not fully recovered yet. We need help and assistance from the international community. They must take action. I want this situation over. I want to go home.”
