[JURIST] UN Secretary-General Ban Ki-moon [official profile] stated [video; transcript] Monday that UN inspectors have confirmed that “chemical weapons were used on a relatively large scale” in the suburbs of Damascus on August 21, causing numerous civilian casualties in violation of international law. A report [text, PDF] issued by chief weapons inspector Ake Sellstrom [official profile], and released by Ban earlier Monday, provides “overwhelming and indisputable” evidence of the use of sarin gas [JURIST report] against civilians in Syria. “The findings are beyond doubt and beyond the pale,” Ban said, reporting that 85 percent of blood samples tested positive for sarin and a majority of rockets and rocket fragments were found to be carrying sarin. Ban also welcomed the agreement between the Russian Federation and the US on a framework to eliminate Syria’s chemical weapons, and urged the Security Council to ensure enforcement and compliance with the plan:

The international community has a responsibility to ensure that chemical weapons never re-emerge as an instrument of warfare … There must be accountability for the use of chemical weapons. Any use of chemical weapons by anyone, anywhere, is a crime. But our message today must be more than: Do not slaughter your people with gas. There must also be no impunity for the crimes being committed with conventional weapons.

However, it is still unclear who is responsible for the chemical attack. Ban concluded that “it is for others to decide whether to pursue this matter further to determine responsibility.”

The Syrian Civil War [JURIST backgrounder] has been ongoing since 2011 when opposition groups first began protesting the regime of Assad. Last week Ban praised [JURIST report] the Syrian government’s formal agreement to sign and abide by the Chemical Weapons Convention (CWC) [text, PDF; OPCD backgrounder]. CWC signatories must agree to “chemically disarm” by destroying chemical weapon stockpiles and creating enforcement mechanisms to ensure that chemical weapons will not be produced, acquired or transferred within their jurisdiction. Rights groups accused [JURIST report] the Syrian government of responsibility for August 21 chemical weapon attacks, which allegedly involved the use of sarin nerve gas. Syria’s main opposition group in August urged the UN [JURIST report] to probe numerous massacres they say were committed during Ramadan by forces loyal to Assad.