BAGHDAD (Xinhua) -- U.S. aircraft launched an air strike on militia positions in downtown Diwaniyah City in south of Baghdad on Saturday, while Iraqi security forces continued clashes with militiamen for a second straight day.

"Iraqi Army and Coalition forces as part of Operation Black Eagle used a strategic air strike to defend against illegally armed militiamen using shoulder-fired rocket propelled grenades," the military said in a statement.

Fixed wing aircraft conducted the air strike after the Iraqi army "made positive identification of the militiamen" before calling for the air strike, it said.

In a separate statement, the military said during the first day, 27 suspected insurgents were detained in the combined operation headed by Iraqi Army troops supported by soldiers and paratroopers from multinational forces.

"Fighting was steady throughout the first day," the statement quoted U.S. military spokesman Maj. Eric Verzola as saying.

Verzola said three anti-Iraqi forces were killed and six others wounded during the operation, whereas two Iraqi soldiers and one coalition soldier were wounded.