Twenty-nine people were killed and 60 others injured Thursday when a suicide attacker detonated explosives amid a crowd of Shi'ite Muslims marking the Ashoura holiday in the northeastern province of Diyala, an Iraqi police source told Efe.

The attack in the village of Zerkush came hours after eight Shi'ite pilgrims were killed and 22 wounded by two bombs that went off in close succession in Al Hafariya, south of Baghdad.

Ashoura commemorates the death of Hussein, grandson of the Prophet Muhammad, nearly 1,400 years ago in the Battle of Karbala, in what is now Iraq.

Hundreds of thousands of Shi'ites take part in mourning ceremonies and many make the pilgrimage to Karbala.

Since the 2003 U.S. invasion, the holiday has become an occasion for Sunni fundamentalists to mount attacks on Shi'ites, who, though dominant in Iraq and Iran, are a minority in the Muslim world as a whole.

Iraqi authorities have implemented additional security measures for Ashoura. EFE