The U.S. military said allied warplanes have bombed Iraqi defense systems in the northern no-fly zone Monday.
The U.S. European Command said planes attacked after Iraq fired anti-aircraft weapons at them during routine patrols.
U.S. and British aircraft patrol the northern no-fly zone often. American planes fly fighter and bombing missions, while British aircraft do reconnaissance.
Such patrols have been going on for years. But they're being watched more closely now that UN weapons inspectors have arrived in Baghdad and Washington has vowed to oust Saddam Hussein.
Iraq considers the patrols a violation of its sovereignty.