Syria attack: Filmmaker's 'aftermath' footage emerges
23 August 2013 Last updated at 19:19 BST
President Barack Obama says the alleged use of chemical weapons in Syria is a "big event of grave concern", although he stopped short of calling for action.
The attack on Wednesday is reported to have killed hundreds of people, including many children.
Mr Obama's comments came as the UK Foreign Secretary, William Hague, placed the blame for the attack on the Syrian government.
Meanwhile, extremely distressing unverified footage is continuing to emerge, including from a Syrian filmmaker.
Bridget Kendall reports.