THE HAGUE: The UN"s chemical weapons watchdog said Tuesday it was checking Kurdish allegations that Turkish forces fired non-conventional weapons in northern Syria, but emphasised it had not launched a formal investigation. "OPCW experts are engaged in the process of assessing the credibility of allegations concerning the situation in Northern Syria," the Organisation for the Prohibition of Chemical Weapons (OPCW) said in a statement. The Hague-based body added however that "the OPCW has not launched an investigation" into charges by Kurdish authorities in northeastern Syria that Turkey has used banned weapons such as napalm and white phosphorus munitions since it launched an offensive there on October 9. Ankara has denied the charges. OPCW specialists continue to collect information "with regard to any alleged use of chemicals as a weapon," the watchdog group said. The Syrian Observatory for Human Rights, which has a network of Syrian sources, has said it could not confirm the use of chemical weapons. Kurdish fighters suffering from burns had reached a hospital in Tal Tamr, near the border town of Ras al-Ain that was bombarded by pro-Turkish forces,, the observatory said. The use of chemical weapons, including substances similar to napalm and phosphorous has been alleged many times since the Syrian conflict began in 2011. Kurdish authorities posted images on social media that showed children suffering from burns that a local doctor said might have been caused by chemical substances. Turkish Defence Minister Hulusi Akar has told reporters that Turkish forces have not resorted to using "chemical weapons."