Did aviation authorities know that this was a dangerous area?
Yes, they most certainly did. Nearly three months ago, on the “Special Rules” section of its site, the U.S. Federal Aviation Administration put out an order prohibiting American pilots, airlines, charter carriers, and everyone else over whom the FAA has direct jurisdiction, from flying over parts of Ukraine.
Anton Gerashenko, an adviser to Ukraine’s Interior Minister, said on Facebook that the plane was flying at an altitude of 33,000 feet when it was hit by a missile fired from a Buk launcher, reported Interfax, a Ukranian news agency.