The men and their warplane were deployed from the 4th Fighter Wing, Seymour Johnson Air Force Base, in North Carolina, the US Defense Department said in a statement.

It warned that coalition forces fighting the war "expects Iraqi forces and Iraqi citizens to abide by all Geneva Conventions relating to the treatment of prisoners.

"Violations of these laws will bring swift and severe consequences," said the statement, which did not specify whether the two were presumed to be prisoners of war.

The cause of the crash was under investigation, it said.

SPACE.WIRE