A U.S. official said on Sunday that Washington had no indication that a drone that had crashed in Iran had actually been shot down.
In Tehran, state television quoted a military source as saying that Iran's military had shot down a U.S. reconnaissance drone aircraft in eastern Iran.
There is absolutely no indication up to this point that Iranians shot down this drone, the official, who declined to be named, told Reuters.
The NATO-led force in Afghanistan said the drone the Iranians claim to have shot down may be an unarmed surveillance drone that was lost last week while flying over western Afghanistan.
(Reporting by David Alexander, Editing by Eric Walsh)