evidence: In April, the International Civil Aviation Organization had warned governments that there was a risk to commercial passenger flights over south-eastern Ukraine.[3]: 217 The American Federal Aviation Administration issued restrictions on flights over Crimea, to the south of MH17's route, and advised airlines flying over some other parts of Ukraine to "exercise extreme caution". This warning did not include the MH17 crash region.[64][65] 37 airlines continued overflying eastern Ukraine and about 900 flights crossed the Donetsk region in the seven days before the Boeing 777 was shot down.[66] Russian air traffic controllers issued a notice effective 17 July at 00:00 with two conflicting altitude restrictions in the airspace in the adjacent area over Russia below 32,000 feet (9,800 m) and below 53,000 feet (16,000 m). Long-distance flights typically travel at altitudes of 33,000 to 44,000 feet,[67] so the second restriction would effectively close that airspace to civilian overflights, but the second restriction was not noted by the automated systems of Malaysian Airlines and the route was not changed. The reason given for the notice was "armed conflict in Ukraine". [...] - ^ Leonard, Peter. "Ukraine: 295 on Malaysia plane shot down over east". Associated Press. Archived from the original on 17 July 2014. Retrieved 17 July 2014.