Iran threatened to shoot down two U.S. Navy surveillance aircraft over the weekend as they were flying over the Strait of Hormuz in the Persian Gulf, a U.S. defense official told CNN.
A Navy P-8 Poseidon with a crew of nine and an Ep-3 Eries with a crew of approximately 24 were in international airspace but "near Iranian airspace."
Iran's territorial waters expand 12 miles into the sea, just like all countries, according to international maritime law.
Three calls to the planes
Iran reportedly made three radio calls to the planes, warning them not to enter Iranian airspace.
The Iranians then threatened to shoot the planes down with surface-to-air missiles if the pilots did not comply.
The U.S. Navy said crews knew they were flying "outside the known range of Iranian air defenses" and continued with their original flight plans.
'Persian Gulf is our house'
This isn't the first time Iran has had unfriendly relations with the U.S. Navy.
According to Business Insider, Iran has previously threatened to close the Strait of Hormuz -- essentially cutting off access to the Persian Gulf.
Prior to this weekend's incident, Tehran unveiled a 180-foot vessel with a banner posted to the side that read: "America should go to the Bay of Pigs, the Persian Gulf is our house" -- a reference to a failed 1961 attempt to overthrow Cuban leader Fidel Castro.
Chief of Naval Operations John M. Richardson told Business Insider the Navy is prepared to respond to being harassed by Iran.
"We always strive to make sure that our commanders have the situational awareness, the capability, and the rules of engagement that they need to manage those situations," Richardson said.
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