Shi'ite Muslim worshippers raise their knives, after cutting themselves to mark Ashura in Sadr City area of Baghdad, 07 Jan 2009

An estimated two million Shi'ites flocked to the central Iraqi city of Karbala for a second day Wednesday to mark the annual religious observance of Ashura.

Men and boys marched down the streets of Karbala, sobbing and cutting gashes in their heads in a ritual to honor the seventh-century death of Imam Hussein, grandson of the Prophet Muhammad.

The rituals took place under unprecedented security after a suicide bombing killed at least 35 people earlier this week near a Shi'ite shrine in Baghdad.

Iraqi officials say the government has deployed more than 30,000 police and soldiers in Baghdad, Karbala, and other parts of Iraq to safeguard the ceremonies.

Ashura marks Imam Hussein's death in battle more than 1,300 years ago and is one of the most important holy days for Shi'ites.

Authorities originally said the Baghdad suicide bomber was a woman. The bombing prompted Baghdad authorities to ban women from nearing the shrine, but Iraqi officials later said the bomber was a man disguised as a woman.

Attacks by Sunni insurgents during Ashura have killed hundreds of people in recent years. But Iraq's majority Shi'ites have turned out in large numbers despite the threat. They have used the occasion to show their strength after decades of oppression under Saddam Hussein's Sunni-led regime.

Some information for this report was provided by AFP, AP and Reuters.