Sarin

The health minister in Turkey, which treated many of the attack's victims and conducted autopsies on others, said test results conducted on victims confirmed sarin gas was used.

Because Syria was not a signatory of the Chemical Weapons Convention, there was no international mechanism to ascribe responsibility for the attack, although UN inspectors did conclude that sarin had been deployed.

Trostianets mayor Yuriy Bova said officials had discovered traces of the deadly substance sarin and other chemical substances. Sarin is a clear and odourless substance that is classed as a potentially lethal nerve agent.