ANKARA, Turkey (AP) _ U.S. fighter planes attacked an Iraqi air defense installation today after being targeted by radar and fired upon by artillery, the U.S. military said.

Air Force F-16s launched a high-speed anti-radiation missile at a radar site near the city of Mosul, after being challenged during a routine patrol of the no-fly zone over northern Iraq, the military said in a statement from Incirlik airbase, southern Turkey.

The jets were unharmed and returned to base safely after the attack about 250 miles north of Baghdad. Damage to the radar site was not immediately known, the statement said.

Incirlik is home to U.S. and British warplanes which enforce the northern no-fly zone, set up after the 1991 Gulf War to protect Iraqi Kurds. A similar no-fly zone in southern Iraq was set up to protect the Shiite minority there.

Iraq does not recognize the zones and has been challenging them since mid-December, triggering retaliatory strikes by U.S. and British jets.

Monday's attack was the first since May 25 when the jets targeted an Iraqi communication installation the U.S. military said was being used to feed information on the location of the allied warplanes.