New York, October 27, 2017 – The United Nations Security Council and Chemical Weapons Convention member countries should take strong measures to ensure accountability after a UN-appointed inquiry found the Syrian government responsible for an April 2017 chemical attack that killed nearly 100 people, Human Rights Watch said today.

The inquiry, known as the Joint Investigative Mechanism, said that it is “confident that the Syrian Arab Republic is responsible for the release of sarin at Khan Sheikhoun on 4 April 2017.” The inquiry also found that the Islamic State (also known as ISIS) had used sulfur mustard, a blister agent, in the village of Umm Hawash on September 15 and 16, 2016.

“The Joint Investigative Mechanism report should end the deception and false theories that have been spread by the Syrian government,” said Ole Solvang, deputy emergencies director at Human Rights Watch. “Syria’s repeated use of chemical weapons poses a serious threat to the international ban against the use of chemical weapons. All countries have an interest in sending a strong signal that these atrocities will not be tolerated.”

The Security Council should move swiftly to ensure accountability by imposing sanctions on individuals and entities responsible for chemical attacks in Syria. Member countries should suspend Syria’s rights and privileges under the Chemical Weapons Convention and formally bring Syria’s violation of the treaty to the attention of the UN General Assembly and the Security Council.

On October 26, the Joint Investigative Mechanism submitted its report on the Khan Sheikhoun attack to the Security Council. Human Rights Watch reviewed a copy of the report.

This report is not the first time the Joint Investigative Mechanism has found that the Syrian government used chemical weapons. The inquiry previously found that government forces carried out chemical attacks on at least three occasions in 2014 and 2015. It also previously found that ISIS used chemical weapons in one case.

The ban on chemical weapons, with 192 member states, is the strongest weapons ban under international law. Human Rights Watch concluded in a report in May that the Syrian government’s widespread and systematic use of chemical weapons could amount to crimes against humanity.

In its report, the Joint Investigative Mechanism said that it was deeply disturbed by the continuing use of chemical weapons: “If such use, in spite of the prohibition by the international community, is not stopped now, a lack of consequences will surely encourage others to follow – not only in the Syrian Arab Republic but also elsewhere. This is the time to bring these acts to an end.”

The UN Security Council created the Joint Investigative Mechanism in August 2015 “to identify to the greatest extent feasible individuals, entities, groups, or governments who were perpetrators, organizers, sponsors, or otherwise involved in the use of chemicals as weapons…in the Syrian Arab Republic.”

Russia supported the resolution creating the Joint Investigative Mechanism, though earlier this week it vetoed a resolution that would have extended its mandate once it expires next month.

Security Council members, including Russia, should renew the inquiry’s mandate so that it can continue its investigations into other alleged chemical weapons attacks, Human Rights Watch said. In a July report, the Organisation for the Prohibition of Chemical Weapons (OPCW) said that a fact-finding mission was investigating the most credible allegations among 60 incidents of alleged chemical weapons use in Syria.

In one of those cases, an attack near the town of al-Lataminah on March 30, five days before the Khan Sheikhoun attack, it has already confirmed the use of sarin, a deadly nerve agent. When its report is finalized, it will send the case to the Joint Investigative Mechanism so it can seek to identify who is responsible for the attack, if the mandate is renewed.

“Russia called for an independent investigation and here is the result,” Solvang said. “The question now is whether Russia will support accountability for the violation of these international norms or whether it will sacrifice principle to protect its Syrian ally.”

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“Death by Chemicals: The Syrian Government’s Widespread and Systematic Use of Chemical Weapons” is available at:

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