Unknown gunmen killed a policeman on Tuesday and injured another two in eastern Baghdad, a security source said.
Gunmen attacked a police patrol in Ghadeer district. They shot dead a policeman and injured another two, the source told the Voices of Iraq (VOI) news agency.
The gunmen escaped to an unknown destination, the source added.
Separately, three civilians were injured when a bomb planted inside a car in Qarada district in central Baghdad exploded, security sources told VOI.
Security forces cordoned off the area of explosion.

Shares fell 2.1 per cent Friday on the Seoul stock exchange on general recession fears. South Korea's won dropped against the dollar.
When the Spirit rover landed on Mars five years ago, no one expected it or its sister rover Opportunity to make it to their first birthdays, let alone their fifth.
Amelie Mauresmo fell victim to a leg injury after less than half an hour on court Friday to hand over a 4-0 victory which put French compatriot Marion Bartoli into the final of the Brisbane International.
Mumbai-based movie Slumdog Millionaire won five prizes Thursday night at the Critics Choice Awards, cementing its position as a surprise favourite just as the Oscar season moves into high gear.
After the Taipei Zoo received two giant pandas from China, another Taiwan zoo said Friday it is seeking to receive a pair of pandas from China.