A suicide bomber blew up his explosive-packed car at a police checkpoint outside a Shi'ite district in northwest Baghdad on Sunday, killing at least seven people and wounding 16 more, police officials said.
Most of the victims of Sunday's bombing were policemen at the checkpoint to the Kadhimiya neighbourhood, where an intelligence service base and the Kadhimiya Shrine, a major Shi'ite Muslim religious site, are located.
Attacks and bombings on Shi'ite and Sunni Muslim areas across the country have killed nearly 2,000 people since April in the worst violence in five years.
Sectarian conflict is intensifying and relations between the country's majority Shi'ite leadership and the Sunni community have deteriorated to their worst since the last American troops left Iraq a year and a half ago.
Conflict in neighbouring Syria, where mainly Sunni rebels are fighting President Bashar al-Assad, a close ally of Shi'ite Iran, is adding to pressure on Iraq's own fragile sectarian and ethnic mix.
No one claimed Sunday's attack, but al Qaeda's local wing, Islamic State of Iraq, often uses suicide bombers in its campaign to provoke all-out conflict of the kind that killed thousands in 2006-2007.