Syria's 'chemical' attack: Distressing footage analysed
22 August 2013 Last updated at 23:44 BST
There is growing diplomatic pressure to allow United Nations inspectors to visit the site of a suspected chemical weapons attack in Syria where hundreds of people are reported to have been killed.
Opposition activists say men, women and children were gassed by government forces near Damascus on Wednesday.
The BBC's Bridget Kendall investigates how the attack unfolded, mainly through extremely distressing videos posted online.