World leaders are facing diplomatic deadlock over Syria, caught between video evidence that strongly suggests a chemical attack, and the absence of concrete evidence.
Footage obtained by ITV News shows the aftermath of the alleged attack: Men, women and children lying dead where they fell.
Whatever killed them will have dispersed quickly, meaning that their bodies are likely to be the only evidence about its nature.
ITV News correspondent Paul Davies reports:
Britain has directly accused the Assad regime of gassing hundreds of Syrian civilians amid warnings only 48 hours remain to find proof.
New videos show the eyewitness accounts of four men who witnessed an alleged chemical attack on Zamalka, a suburb of Damascus.
These are the images of the remains of rockets which, according to the men stood by them, delivered poisonous gas to a suburb of Damascus.