NEW YORK • United Nations Secretary-General Ban Ki Moon has told the Security Council that he is planning to set up a three-person team to investigate alleged chemical weapons attacks in Syria.

The move came amid new reports of a mustard gas attack in the country that activists said could have been carried out by the Islamic State in Iraq and Syria (ISIS).

The investigative panel will seek to identify who is behind the attacks, in line with a UN resolution adopted this month to establish responsibility for the use of the banned toxic agents. Mr Ban described the panel's mission in a seven-page letter and will await the council's green light before launching a recruitment drive for top experts to carry out the mission.

Doctors Without Borders earlier this week said it had treated civilians suffering from apparent exposure to a chemical agent in Marea, a town near the northern city of Aleppo, after an attack last week. The Syrian American Medical Society said its doctors had identified the agent as mustard gas. Recently, reports emerged that ISIS extremists may have used mustard gas against Iraqi Kurdish fighters.

"The continuing reports of the use of chemical weapons, as well as the use of toxic chemicals as a weapon in the Syrian conflict are deeply disturbing," Mr Ban said in a separate statement on Thursday. "The international community has a responsibility to hold the perpetrators accountable and to ensure that chemical weapons never be used again as an instrument of warfare."

Earlier this month, the 15-member council unanimously endorsed the resolution setting up the joint investigative mechanism that will work with the Organisation for the Prohibition of Chemical Weapons. That inquiry will seek "to identify to the greatest extent feasible individuals, entities, groups or governments who were perpetrators, organisers, sponsors... involved in the use of chemicals as weapons" in Syria, said Mr Ban. The team will have "full access to all locations" and "may establish contact and receive information from any parties" in Syria.

AGENCE FRANCE PRESSE