Two car bombs exploded almost simultaneously at separate sites in this mostly Shiite city early Tuesday, wounding at least three people, police said.

The blasts were detonated by remote control and were about five minutes apart, said police Capt. Muthana Khalid.

The first went off on a road on the northern side of the city, hurting no one, Khalid said.

Five minutes later, the second car bomb exploded at a bustling market, injuring at least three people, Khalid said.

Hillah, 60 miles south of Baghdad, has suffered repeated attacks. It is also the site of the single deadliest attack in the two-year insurgency, a homicide car bombing outside a medical clinic on Feb. 28, 2005 that killed 110 people.

Also Tuesday, police said four Iraqi officers were killed in two separate attacks on police patrols in Baqouba and Beiji, north of Baghdad. The assailants were not identified.