Iraqi insurgents have attacked a number of police stations near Baquba, north of Baghdad, police say.
They say at least 11 officers were wounded - although Reuters news agency speaks of 45 police deaths.
The group led by Jordanian-born militant Abu Musab al-Zarqawi - which is believed to have links with al-Qaeda - says it carried out the attacks.
Baquba, a mixed Sunni and Shia town 65km (40 miles) from Baghdad, has been a centre of anti-US resistance.
In July, about 70 people were killed when a car bomb exploded outside a police station in the town, one month after the transfer of sovereignty.
In the latest attacks early on Tuesday, militants using rifles and rocket-propelled grenades stormed two police stations
in the Baquba region, officials said.
One of the buildings was completely destroyed, AFP news agency reports.
The attacks come as US and Iraqi forces continue their efforts to recapture Falluja, a city west of Baghdad held by Sunni insurgents.