The Iranian government announced on state TV that it has shot down an unmanned military drone in eastern Iran.

Reuters:

Iran's military said on Sunday it had shot down a U.S. reconnaissance drone aircraft in eastern Iran, a military source told state television.

"Iran's military has downed an intruding RQ-170 American drone in eastern Iran," Iran's Arabic-language Al Alam state television network quoted the unnamed source as saying.

"The spy drone, which has been downed with little damage, was seized by the Iranian armed forces."

Iran shot down the drone at a time when it is trying to contain foreign reaction to the storming of the British embassy in Tehran on Tuesday, shortly after London announced that it would impose sanctions on Iran's central bank in connection with Iran's controversial nuclear enrichment program.

Most of Iran's nuke facilities are located in southern and central Iran so it is unlikely a drone would be spying on those. However, eastern Iran is where it is thought some al-Qaeda leaders are hiding so it is more probable that we're looking for targets.

Of course, it's impossible to confirm whether the Iranians are telling the truth or not. We'll never tell and Iran's reputation for accuracy is wanting. Nevertheless, it is slightly worrying that Iran might be able to track our drones. It shows a sophistication in air defense that we may not have realized.