What we know about the April 4 chemical attack in Syria

The April 4, 2017 chemical attack on the rebel-held town of Khan Sheikhoun in Syria led to at least 70 deaths and more than 100 people requiring medical attention, prompting an outcry from the international community. It led to the April 7 US bombing of the Shayrat air base. It is alleged that sarin was used in the Khan Sheikhoun attack. This particular chemical became famous in 1995 with the