The British delegation at the world’s chemical weapons watchdog said on Thursday that samples taken from the alleged chemical weapons attack in Syria’s rebel-held Idlib province last week tested positive for the nerve agent sarin.
The toxic gas attack in Idlib’s Khan Sheikhoun on April 4, which killed scores of children, prompted the United States to launch missile strikes on an air base in Shayrat that lies in central Syria’s Homs and widened a rift between Washington and Moscow, a close Syrian ally.
“UK scientists have analyzed samples taken from Khan Sheikhoun. These have tested positive for the nerve agent sarin, or a sarin-like substance,” the delegation said during a special session at the Organization for the Prohibition of Chemical Weapons in The Hague.
Earlier testing by Turkish authorities had also said the chemical used in the attack was sarin.
A fact finding mission from OPCW was sent to Turkey to gather bio-metric samples and interview survivors, sources told Reuters earlier Thursday.
The OPCW mission will determine whether chemical weapons were used, but is not mandated to assign blame. Its findings, expected in 3-4 weeks, will be passed to a joint United Nations-OPCW investigation tasked with identifying individuals or institutions responsible for using chemical weapons.
Last week’s bombing in the town of Khan Sheikhoun near the Turkish border was the most lethal since a sarin attack on Aug. 21, 2013 killed hundreds in a suburb of the capital, Damascus.
On the battlefield, US-backed forces fighting ISIS launched a new phase of their offensive on Thursday, a statement said, but they have not yet begun to attack the militant group’s stronghold of Raqqa city in an apparent delay in the operation.
The multi-phased campaign by the Syrian Democratic Forces (SDF), an alliance made up of Syrian Kurdish and Arab fighting groups, was launched in November and aims ultimately to drive the jihadists from Raqqa, their de facto Syrian capital.
Officials in the Kurdish YPG militia, a powerful component of the SDF, said last month that assaults on Raqqa city itself would start in early or mid-April.
But the fourth phase of the campaign aims to clear ISIS pockets from the countryside north of the city, the SDF statement said. It did not say when the assault on Raqqa itself would begin.
“We aim to liberate dozens of villages in the Wadi Jallab area and the northern countryside … and clear the last obstacles in front of us to pave the way for the operation to liberate Raqqa city,” it said.
The SDF have closed in on Raqqa from the north, east and west.