This is just developing, so I can’t vouch for its accuracy at this time.
From The Independent (UK)
“The Syrian army has accused the US-led coalition of launching an air strike on Wednesday evening that hit an Islamic State chemical weapons supply, killing "hundreds including many civilians"….
Syrian state-owned news agency Sana reported the air strike, on the village of Hatla, as a “white cloud that became yellow as a result of the explosion of a huge store that includes a large amount of toxic materials.
There was no immediate independent confirmation or reaction from the US coalition, which has operated in the skies above Syria since 2014.”
This report from Public Radio of Armenia provides a few more details.
“The jets of the so-called US-led coalition launched a strike at about 17:30-17:50 [local time, 14:30-14:50 GMT] on a Islamic State (IS) warehouse where many foreign fighters were present. First a white cloud and then a yellow one appeared at the site of the strike, which points at the presence of a large number of poisonous substances. A fire at the site continued until 22:30 [19:30 GMT],” the Syrian army’s command statement obtained by Sputnik said.”
As I said, these are early reports and will undoubtedly be added to during the day.
Next up, John McCain will claim Assad put the gas under the coalition bombs???
Map of Deir ez-Zur, Syria: