The attacks in the Abu Dsheer district came amid political tensions as a Sunni-backed alliance which came first in an inconclusive election in March accused Shi'ite-led factions of trying to deprive it of the right to form the next government.

The suicide bombers in two cars drove at two checkpoints at more or less the same time, and blew themselves up, a police source said.

The blasts also followed a string of battlefield successes in recent weeks against al Qaeda in Iraq, including the killing of its top leaders on April 18.

Last Friday car bombs planted in Shi'ite neighborhoods of Baghdad killed dozens.

Security officials said last week's bombings were likely revenge attacks for the deaths of al Qaeda's leader in Iraq, Abu Ayyub al-Masri, and Abu Omar al-Baghdadi, the purported head of its affiliate, the Islamic State of Iraq.

Reuters