Security forces in Iraq have been placed on alert on the first anniversary of the execution of former President Saddam Hussein.

His supporters are expected to gather at his power base in the city of Tikrit, and at his grave nearby.

Saddam was hanged after being convicted of the killings of nearly 150 Shia Muslims in Dujail in the 1980s.

He was taunted by his executioners shortly before his death, conduct which embarrassed the Iraqi government.

Scenes from the execution were captured on mobile telephones and quickly distributed around the world, prompting US President George W Bush, among others, to criticize the way the death sentence was carried out.

The killing of the 69-year-old Sunni leader worsened the rift with Shia groups in Iraq.

Iraqi officials conceded that some supporters would visit the grave where Saddam is buried next to his sons Uday and Qusay, who died in a gun battle with US forces in 2003.