Both the Syrian regime and its ally Russia have blamed “terrorist groups” Damascus formally requested the Organization for the Prohibition of Chemical Weapons (OPCW) in The Hague investigate the alleged attack on Saturday THE HAGUE: The world’s chemical watchdog said Monday it was reviewing security ahead of a possible probe into an alleged chemical attack in Syria’s regime-held city of Aleppo over the weekend. Damascus formally requested the Organization for the Prohibition of Chemical Weapons (OPCW) in The Hague investigate the alleged attack on Saturday which Syrian officials and rights groups said left scores of people struggling to breathe. Both the Syrian regime and its ally Russia have blamed “terrorist groups” — a term which Damascus uses to mean both rebels and militants. The alleged attack also prompted Russia to launch retaliatory air strikes into a planned buffer zone near the last major opposition stronghold of Idlib. “The OPCW Secretariat has been monitoring the situation,” said director-general Fernando Arias. It has contacted the UN’s security department “in order to assess the security situation on the ground for a possible deployment of the Fact-Finding Mission (FFM) to Syria,” the OPCW director-general said. The body’s Secretariat implements the OPCW’s verification measures while the FFM, set up in 2014, investigates all allegations of chemical weapons use in war-torn Syria. “The OPCW’s experts will continue to work independently to verify all allegations of the use of chemicals as weapons in Syria,” Arias told delegates at a nine-day conference to review the world body’s strategy for the next five years. Syria again Monday blamed “armed terrorist groups” for launching a toxic gas attack which it said left around 100 Syrians hospitalized with breathing difficulties. “It is believed that the agent used was chlorine,” said Bassam Al-Sabbagh, Syria’s permanent representative to the OPCW. “We have discussed the potential of launching an investigation into this attack to find out what exactly happened in the city of Aleppo,” he told the delegates. Russia said the shelling came from an area of the buffer zone controlled by the jihadist-dominated Hayat Tahrir Al-Sham (HTS) alliance. A rebel coalition has denied any involvement, but neither the HTS, nor the Al-Qaeda-linked Hurras Al-Deen group present in the area have commented on Saturday’s alleged attack. It was the latest accusation of a chemical attack in Syria’s grinding seven-year civil war, which has killed more than 360,000 people and displaced millions.