HOLY KARBALA, Iraq: Iraqi authorities have launched a major operation to protect pilgrims attending one of the world's largest religious events - Ashura.

Black-clad mourners are converging on the city, 110 km (70 miles) south of Baghdad, for Ashura which climaxes on Sunday January 20 this year.

The mourners carried red and black flags, while buildings were draped in black cloth in mourning for Imam Hussein.

"I have come with my husband and two children despite the chilly weather. Attending Ashura is part of our culture and nothing on earth would stop us from showing our grief," said Ahlam Nima Jasim, 30, from Diwaniya, 120 km to the southeast.

Saddiq al-Hir, head of Kerbala's tourism association said for the first time in years murners include visitors from the Gulf states of Kuwait, Bahrain and Saudi Arabia.

A vehicle ban has been imposed in the city, snipers have taken up positions on rooftops, roadblocks set up, and 25,000 soldiers and policemen deployed while Iraqi aircraft keep watch from above for the first time.

Some 4,000 policemen have been deployed on the road between Kerbala and Najaf.

Many mourners are walking on foot from towns and cities, including the capital.

The authorities have already ordered motorbikes off the streets of the capital for fear they could be rigged with explosives and used against pilgrims, who are also prohibited from carrying mobile phones or being accompanied by children.