On July 21, 2014, the UN Security Council adopted Resolution 2166 in response to the downing of Malaysian Airlines Flight MH17 in Ukraine on July 17, 2014. Condemning “in the strongest terms the downing of” the flight, the resolution “[r]eaffirm[s] the rules of international law that prohibit acts of violence that pose a threat to the safety of international civil aviation,” and  “[d]emands that those responsible for this incident be held to account and that all States cooperate fully with efforts to establish accountability.” As such, the Security Council “demands that the armed groups in control of the crash site and the surrounding area refrain from any actions that may compromise the integrity of the crash site. . . and immediately provide safe, secure, full and unrestricted access to the site and surrounding area for the appropriate investigating authorities.”