Syrian rebels have posted a number of videos purporting to show the impact of a second chemical weapon attack in Damascus.
Residents reported that the attack took place during morning prayers yesterday, and approximately 400 people were showing "signs of exposure to chemical toxic gases."
ITV News cannot independently verify the social media content.
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Andreea Cristea, 29, remains in a critical condition after being rescued from the Thames after a terror attack along Westminster Bridge.
The Prime Minister has praised the former soldier's "huge professionalism" in trying to save the life of Pc Keith Palmer.
The man who carried out the Westminster attack is thought to be British born and was once investigated by MI5, the Prime Minister has said.