Here is a headline timeline in EST:
10:22 a.m. Reuters confirms the plane has crashed
10:38 a.m. Bloomberg News reports the plane has vanished
10:39 a.m. BBC reports the plane is missing
10:41 a.m. CNN says the plane is "lost" and "off radar"
10:42 a.m. Washington Post reports the plane has vanished
10:44 a.m. New York Times has no mention of it on its website
10:50 a.m. Wall Street Journal reports the crash
10:52 a.m. Reuters was added to my "favorites"