A Malaysia Airlines passenger plane was flying in open airspace, but about 1,000 ft above a closed section, the European organisation for the safety of air navigation Eurocontrol has said.
"According to our information, the aircraft was flying at Flight Level 330 (approximately 10,000 metres/33,000 feet) when it disappeared from the radar," Brussels-based Eurocontrol said.
"This route had been closed by the Ukrainian authorities from ground to flight level 320 (approximately 32,000 feet) but was open at the level at which the aircraft was flying." Since the crash, all airspace in eastern Ukraine has been closed up to an unlimited height.
Thousands of online users have taken to social media to call for the victims of the Malaysian airliner crash to be returned to loved ones.
United States intelligence officials admitted that they do not know who fired the surface-to-air missile that downed flight MH17.
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