The U.S. has closed 19 embassies across the Middle East and Africa through this week in response to the threat. Most personnel were evacuated from the U.S. Embassy in Sanaa, Yemen, on Tuesday.
The terror threat prompting the embassy closures was uncovered after U.S. intelligence reportedly intercepted a message between the leader of al Qaeda Ayman al-Zawahri and the head of AQAP, Nasir al-Wuhayshi.
The AP reported that a drone was buzzing over Sanaa for hours Wednesday and early Thursday.
The first attack targeted a vehicle carrying suspected militants in the district of Wadi Ubaidah, roughly 100 miles east of Sanaa, according to the AP.