Turkey has now been accused of using white phosphorous, and Newsweek has obtained photos that may show evidence of that.

The reports emerge from Kurdish-led forces battling Syrian insurgents backed by Turkey, a fight between two U.S. allies that has compelled President Donald Trump to withdraw troops from the country. Though the mostly Kurdish fighters of the Syrian Democratic Forces assisted the Pentagon in battling the Islamic State militant group (ISIS), the partnership did not extend to fighting Turkey, a NATO member allied with various Syrian insurgent groups.

White phosphorous is not technically illegal, as its widely used for flares or smokescreens, but Protocol III of the Convention on the Prohibition of Use of Certain Conventional Weapons restricts its use in heavily-civilian-populated areas. Many countries, including the U.S., have continued to do so, however.

Danish freelance journalist Thea Pedersen, who documented the alleged white phosphorous burn victims at hospitals in northeastern Syria, described to Newsweek graphic scenes of discolored, dead skin that, despite decades of experience, doctors said they “had never seen before.”

Pedersen cited one of several doctors as saying “we need experts to verify this, but it’s abnormal.”

Pedersen’s photos, shown below, document the horrific burns and injuries.