DUBAI, United Arab Emirates (AP) — The U.S. Navy says it had a second tense encounter with an unarmed Iranian drone in the Persian Gulf in recent days.

The 5th Fleet in Bahrain said Tuesday the encounter involved the USS Nimitz aircraft carrier and an Iranian Sadegh drone.

Lt. Ian McConnaughey, a 5th Fleet spokesman, said the drone was following the Nimitz and other ships during flight operations Monday night.

McConnaughey says the drone "did not use any aircraft navigation lights while it made several passes in close proximity to Nimitz and its escort ships during active flight operations, coming within 1,000 feet (300 meters) of U.S. aircraft."

McConnaughey says the drone was unarmed. That model can carry missiles.

Another Iranian drone came close to a U.S. fighter jet on Aug. 8.