Pentagon officials said that Iraq sent aircraft to investigate the flight, contending that only one of the two planes was authorized to enter its airspace.
Air controllers withdrew the U-2s into the southern "no-fly" zone over Iraq, where coalition warplanes could more easily protect them. The surveillance planes returned to their base without incident.
A senior Bush administration official said that Iraq threatened the aircraft.
The official said U.N. Security Council Resolution 1441, which sent weapons inspectors back to Iraq, allows multiple surveillance flights, "but when Iraq found two of them, they threatened them, and they had to return and land."
The official said the United States is trying to seek more information from U.S. personnel and the U.N. Monitoring, Verification and Inspection Commission, the U.N. weapons inspection agency.
It was not clear when the surveillance flights would resume.
Hmmm...