In the war's second friendly fire incident, an American F-16 fired on a U.S. Patriot missile battery in Iraq after the battery's radar locked on the jet, U.S. Central Command said Tuesday. No U.S. casualties were reported.
Monday's incident occurred about 30 miles south of Najaf, said Lt. Mark Kitchens, a U.S. Central Command spokesman. The F-16 fired an AGM-88 high-speed anti-radiation missile at the battery and damaged its radar, he said.
On Sunday, a U.S. Patriot missile battery shot down a Royal Air Force Tornado GR4 near the Kuwaiti border, killing the two crew members.
Kitchens said Monday's strike was under investigation "to identify procedural changes to ensure the safety of our air crews and Patriot crews in combat operations," he said without elaborating.
It wasn't clear what caused it, but Kitchens said "all parties involved executed according to their training."
He acknowledged the similarity to the one involving the RAF aircraft but denied it indicated a failure on the part of the Patriot system or its ability to tell friend from foe.
"The two incidents are separate and distinct and both are under review," he said.
In Sunday's incident, a U.S. Patriot battery intercepted the British Tornado as it was returning from a mission to strike Republican Guard targets near Baghdad.
Analysts said that interception was unusual because coalition aircraft would have all been outfitted with an Identify Friend or Foe system signal that is compatible with all member countries of the coalition. The IFF, also used in civil aviation, sends an automatic response when a radar system queries it.
Kitchens said it wasn't clear if an IFF failure was responsible for Monday's incident.
The RAF shootdown caused the first confirmed deaths from friendly fire in the war against Saddam Hussein's regime.