UNITED NATIONS (AP) — Ukraine’s ambassador to the U.N. says the downing of the Malaysian airliner would not have happened if Russia did not provide sophisticated anti-aircraft systems to separatist rebels.

Ambassador Yuriy Sergeyev told an emergency meeting of the U.N. Security Council on Friday that communications and intercepts, photos and videos indicate that the rebels have at least two SA-11 missile systems.

He added that detained rebels have told Ukraine that they also have a Buk missile system from Russia.

Sergeyev said that immediately after the crash, a rebel military leader had boasted in social media of shooting down what he thought was a Ukrainian jet.

He also said that in previous days, rebels had shot down two Ukrainian jets, and claimed responsibility in intercepted telephone conversations with a Russian military intelligence colonel.

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