U.S. officials don't dispute Iraq's story that it shot down the reconnaissance plane, but a spokesman says it's also possible the crash was the result of a technical failure.
In a brief statement from U.S. Central Command headquarters at MacDill Air Force Base, Fla., Col. Rick Thomas, said it was not yet clear why the plane was missing.
"The aircraft may have crashed or been shot down," Thomas said.
A Pentagon spokesman, Marine Corps Lt. Col. David Lapan, said it was not possible to determine conclusively from the images shown by Iraqi television whether the wreckage was that of a U.S. aircraft.
The U.S. has no plans to attempt to recover the $3.2 million RQ-1B Predator aircraft, which was lost near the heavily defended city of Basra.
"No sensitive technology will be compromised by not recovering the aircraft," Thomas said.
In Iraq, government newspapers trumpeted the first downing of a U.S. aircraft since the 1991 Gulf War, calling it a "slap for American aggression."
"Iraqi skies are a death zone for the enemy," said Al-Jumhuriya newspaper.
Also on Monday, U.S. planes attacked a SA-3 surface-to-air missile site in northern Iraq, a U.S. official said. The U.S. European Command, which is responsible for U.S. operatons in northern Iraq, said in a brief statement that U.S. planes retaliated when Iraqi forces fired anti-aircraft artillery from sites north of Mosul.
The United States has lost Predator reconnaissance planes to hostile fire before, mainly in the Balkans, but rarely if ever over Iraq.
Ret. Air Force Maj. Gen. Perry Smith, a CBS News military consultant, notes, however, that sometimes the Predator crashes without having been shot down.
"There have been a number of cases where the Predator, both in training and in combat has crashed into the ground not because it was shot down, but because it had a mechanical failure of some type and it crashed," says Smith.
Whether the Predator was shot down or crashed due to a technical failure, it was the first American aircraft of any kind to be lost in Iraq since the accidental shootdown of two U.S. Army helicopters by U.S. Air Force F-15 fighters in 1994.
In July, an Air Force U-2 surveillance plane was rocked by the concussion from an Iraqi surface-to-air missile. The U.S. plane was not hit but the missile explosion was close enough to be felt by the crew.
U.S. and British forces began monitoring no-fly zones over Iraq a decade ago.
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