The US Navy says the single-seat F/A-18E and two-seat F/A-18F "were providing en route close air support from Iraq when they crashed". The aircraft were from Carrier Air Wing (CVW) 3.
Currently deployed on the Truman, CVW-3 includes strike fighter squadrons VFA-11 and VFA-32 operating the F/A-18F, VFA-105 with the F/A-18E, and VFA-37 with the earlier F/A-18 Hornet.
USS Truman prepares to launch an F/A-18F © US Navy
The US Navy says the cause of the accident is under investigation, and makes no mention of collision or hostile fire. Two USN F/A-18Fs crashed into the sea off Monterey, California on 18 October 2002.