REUTERS/Maxim Zmeyev
Emergencies Ministry members walk at the site of a Malaysia Airlines Boeing 777 plane crash in the settlement of Grabovo in the Donetsk region, July 17, 2014.
Fox is citing the flight manifest that reportedly lists 23 Americans, and Reuters cites an Interior Ministry adviser quoted by Interfax.
The U.S. State Department has not yet confirmed whether there were any Americans on board the plane.
The Boeing 777 plane was flying from Amsterdam to Kuala Lumpur when it crashed in eastern Ukraine about 25 miles from the Russian border. There were 295 people on board.