Police said this morning at least 15 people were killed when a car bomb exploded near a sacred Shia shrine in the southern Iraqi city of Najaf.
The blast at the Imam Ali shrine, which is sacred to Shias, came at a highly sensitive time when Iraqi leaders are struggling to form a government four months after parliamentary elections, raising fears that the deepening political vacuum will fuel sectarian violence.
Such attacks are rare in Najaf, which is tightly controlled by police and Shia security guards. Iraqi Shias consider any attacks within Najaf as a grave provocation.
Pressure is mounting on Prime Minister Ibrahim al-Jaafari to step down and break a deadlock over the new government.
But he refuses to heed calls by Sunni Arab and Kurdish rivals and even senior members of his own Shia alliance to withdraw his nomination for the next cabinet.
The crisis has exposed deep divisions among Iraq's ruling Shias, who dominate the government and are backed by militias.