Authorities in Kurdish-controlled areas in Syria have accused Turkey of using unconventional weapons such as white phosphorus and napalm during its offensive in the northern areas of the country, AFP reported.

The agency says it has failed to independently verify these allegations against Ankara forces or Syrian fighters who support them.

Since the start of the offensive against Kurdish militia, Turkish troops and their Syrian allies (part of rebel groups fighting the Bashar al-Assad regime) have seized a 120-km-wide border in northern Syria and fighting is now under way in the city of Ras al Ain.

"The Turkish aggression is using all available weapons against Ras al-Ain," the Kurdish statement said." the semi-autonomous Kurdish administration said in a statement today.

Syrian Observatory for Human Rights, which has an extensive network of on-field informants, could not confirm that such weapons were being used. However, human rights activists have registered people with burn injuries that have arrived at the Tell Tamer Hospital in the past two days, the NGO director Rami Abdel Rahman told AFP.

Kurdish officials posted footage on social media showing children with burns, who, according to a Hasaka province doctor, may confirm that such weapons were used.

"Faced with the obvious failure of his plan, Erdogan is resorting to weapons that are globally banned such as phosphorus and napalm," the statement added.

"There are a lot of fears that prohibited weapons are being used in Sari Kani. Wounds we treat at the hospitals are not normal injuries at all," Dr. Manal Mohammed, head of the Rojava Health Board, told Rudaw on Wednesday night.

"Our health board is currently investigating to find out what type of weapon is being used against us. Like I said, wounds we treat are not normal at all,” the doctor said, Rudaw reported.

"We urge international organisations to send their teams to investigate some wounds sustained in attacks," Mustefa Bali, spokesman for the Syrian Democratic Forces (UDF), Kurdish-Arab Coalition, said on social media.