<P> The Khan Shaykhun chemical attack took place on 4 April 2017 on the town of Khan Shaykhun in the Idlib Governorate of Syria . At the time of the attack, the town was under the control of Tahrir al - Sham, previously known as the al - Nusra Front . </P> <P> The town was reported to have been struck by an airstrike by government forces followed by massive civilian chemical poisoning . The release of the toxic gas, which included sarin, or a similar substance, killed at least 74 people and injured more than 557, according to the Idlib health authority . The attack was the deadliest use of chemical weapons in the Syrian civil war since the Ghouta chemical attack in 2013 . </P> <P> The governments of the United States, United Kingdom, Turkey, Saudi Arabia, France, and Israel, as well as Human Rights Watch, attributed the attack to the forces of Syrian President Bashar al - Assad . The Assad government denied using any chemical weapons in the air strike . The Russian Defense Ministry stated that Syrian aircraft had bombed a warehouse belonging to rebels which "may have contained a rebel chemical arms stockpile". </P> <P> On 7 April, the United States launched 59 cruise missiles at Shayrat Air Base, which U.S. intelligence claimed was the source of the attack . </P>

Who did the chemical gas attack in syria
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