BAGHDAD, Iraq (CNN) -- At least 12 prisoners died in separate attacks on detention centers in the Iraqi capital, one involving mortars and the other involving rockets, Iraqi and U.S. officials said Monday.
Seven prisoners were killed when mortars slammed into a detention center in central Baghdad operated by the Iraqi Interior Ministry, a ministry official said. At least 23 people, including five police officers, were wounded in the attack, the official said.
Five more detainees were killed at a holding cell on a forward operating base in eastern Baghdad's Rusafa district, the U.S. military said. Nine 122 mm rockets were fired at the facility, at least one of which was on target.
Twenty-five people were wounded in the attack, the military said.
In central Baghdad's Karrada district, separate attacks left several people dead or wounded, the Interior Ministry official said. Two civilians were killed when gunmen fired into their car from another vehicle, the official said. In another attack, two mortars landed in Karrada, wounding three civilians.
In eastern Baghdad's Baladiat neighborhood, five people -- four of them police officers -- were wounded when a roadside bomb detonated near an Iraqi national police convoy, the official said.
In southern Baghdad, a fire erupted at the Dora oil facility, one of Iraq's main refineries fueling Baghdad's power plants. No injuries were reported.
Conflicting stories emerged about how the fire started, with U.S. and Iraqi officials saying it was sparked by an accidental pipeline explosion. But Oil Ministry spokesman Assem Jihad said he was at the refinery hours after the incident and workers there confirmed the facility had been attacked.
The fire was contained, Jihad said, but it continued to burn 4 million liters (more than 1 million gallons) of benzene, a carcinogenic and highly flammable liquid used in oil refineries. He stressed that the fire has not affected the refinery's production. E-mail to a friend
CNN's Yousif Bassil and Jomana Karadsheh contributed to this report.