Click on the 'Listen' button above to hear this interview.  More than 60 people have been killed in a suspected chemical attack in the Idlib province of rebel-held northern Syria. It is being called one of the largest toxic gas attacks in the ongoing conflict.    Doctors at the scene say victims have been showing symptoms similar to those caused by exposure to sarin gas. There are reports that after the initial chemical attack, a series of airstrikes targeted a hospital and emergency clinics where victims were being treated.   For details on this story we turn to Louisa Loveluck, Middle East correspondent for The Washington Post who has reported extensively on Syria.Â