Iran reportedly threatened to shoot down two US Navy spy planes as they flew over international waters in the Persian Gulf this weekend.
US defense officials told Fox News a Navy P-8 Poseidon aircraft and a EP-3 Eries were warned if they didn't change course they would be shot down.
The military planes were on a reconnaissance mission 13 miles off the coast of Iran on September 10 when the incident occurred, meaning they were just one mile outside Iran's territorial waters.
International maritime law says nations can have a belt of waters extending 12 nautical miles from the coast.
'We wanted to test the Iranian reaction. It's one thing to tell someone to get off your lawn, but we weren't on their lawn. Anytime you threaten to shoot someone down, it's not considered professional,' an official told Fox News.
