US troops in Iraq say they have killed an al-Qaeda leader who masterminded the attacks on a Shia shrine that led to a major escalation in sectarian violence.
Officials say Haitham al-Badri was behind the 2006 and 2007 attacks on the al-Askari shrine in Samarra, which destroyed its golden dome and minarets.
The US said al-Badri was the leader of al-Qaeda in Salahuddin province.
The US claim came as mortar attacks killed at least 11 people in the eastern part of the capital, Baghdad.
According to US officials, Mr al-Badri was killed on Thursday during a US operation east of Samarra.
Unconfirmed reports say he was killed in an air strike.
A BBC correspondent in Baghdad, Andy Gallacher, says the Iraqi government has always blamed Mr al-Badri for the February 2006 attack on the mosque, which is seen by many as a turning point in the sectarian violence.
The mosque is one of the most sacred Shia sites in Iraq, and the attacks set off a wave of sectarian violence which claimed the lives of thousands of civilians.
A second attack, in June 2007, saw its ancient minarets destroyed.
Meanwhile, violence claimed more lives on Sunday in east Baghdad, when a barrage of mortar rounds fell on a petrol station crowded with Iraqis queuing for fuel at dawn, killing at least 11 people, wounding 15 and destroying cars.
Mortar rounds also fell at another petrol station nearby, wounding six more people.
Shortages mean Iraqis often have to line up for hours for fuel, where they are frequently targeted.