Dozens of people have been killed in a suspected chemical attack in rebel-held northern Syria, in one of the largest mass casualty incidents using a toxic gas in the six-year conflict.

The death toll rose to 67 in the hours after the attack on Khan Sheikhun in Idlib province on Tuesday morning. Doctors said the victims exhibited symptoms apparently matching those caused by exposure to deadly sarin gas. Scores more people were injured.

The raids were carried out by planes believed to be loyal to the government of Syrian president Bashar al-Assad. Later, a series of airstrikes on the same town targeted a hospital and two emergency response centres that were recovering and treating victims of the initial strike.

The attack came a day after the US ambassador to the UN, Nikki Haley, said the US government was no longer focused on Assad’s removal from office, and as a two-day conference on Syria’s future, hosted by the EU and UN, began in Brussels.

The international chemical weapons watchdog said it was gathering and analysing information. The French foreign minister, Jean-Marc Ayrault, demanded an emergency UN security council meeting.

Khan Sheikhun houses thousands of refugees from the nearby province of Hama who have fled the fighting there

MORE:   https://www.theguardian.com/world/2017/apr/04/syria-chemical-attack-idlib-province