The Islamic State (ISIS/ISIL or Daesh) might be using chemical weapons in Syria, a senior Russian official claimed Tuesday.

Mikhail Ulyanov, who heads the Russian Foreign Ministry's department for non-proliferation and arms control of mass destruction, claimed that there was a high probability of chemical weapon use by ISIS and other extremists groups in Syria.  

"Several times we have noted facts of the probable use of chemical weapons by IS militants and in a broader sense by Islamic radicals, beginning with the attack in (the Syrian city) of Khan al-Assal in March 2013 against government forces," Ulyanov told RIA Novosti, according to Sputnik News.

He also demanded an investigation into Turkey's involvement in shipment of toxic sarin gas to Syria.

The Russian diplomat's remarks came after the Organization for the Prohibition of Chemical Weapons (OPCW), the U.N.'s chemical weapon monitoring agency, found evidence of sarin gas used by radicals in Syria.

"In one instance, analysis of some blood samples indicates that individuals were at some point exposed to sarin or a sarin like-substance," OPCW chief Ahmet Uzumcu said in the organization's monthly report, according to RT.

The U.N. body also declared in its monthly report on Monday that a U.S. company has completed the disposal of the Syrian chemical weapon arsenal. Seventy-five cylinders of hydrogen fluoride were destroyed by the firm at its Texas facility.

"This process closes an important chapter in the elimination of Syria's chemical weapon programme as we continue efforts to clarify Syria's declaration and address ongoing use of toxic chemicals as weapons in that country," Uzumcu said, according to CNN.