HOLY CITY OF KARBALA, Iraq: Karbala governorate council announced that more than four million people descended on the holy city of Karbala on Friday December 17 to commemorate Ashoura al-Imam Al-Hussein (AS) amid tight security.

Mourners from across Iraq, along with tens of thousands of foreign pilgrims -- most dressed in black -- streamed into Karbala to mark the darkest day of human history when some 1400 years ago Sibt an-Nabi (son of Prophet Muhammad, peace be on him and his holy progeny) al-Imam Abi Abdellah Al-Hussein (AS) was brutally and unjustly slaughtered at the hands of the then ruler Yazid.

Marking Ashoura, the mourners beat their heads and chests and gash their heads with swords to mourn the slaying of Imam Hussein (AS).

Security officials assigned thousands of police officers and soldiers to protect the pilgrims as they headed to Hussein's shrine in Karbala, 80 km (50 miles) southwest of Baghdad. Authorities imposed a city-wide ban on cars and motorcycles to help prevent attacks.

Securing the event was a key test for Iraqi security forces, who have taken over responsibility for protecting the country as U.S. troops withdraw 7-1/2 years after the U.S.-led invasion and with no new government in place nine months after an inconclusive parliamentary election.

"More than 28,000 police officers have been deployed to protect pilgrims in addition to the troops that support security in the towns around Karbala," Major-General Othman al-Ghanimi, chief commander of the Iraqi army in Kerbala, told Reuters.

Prime Minister Nuri al-Maliki thanked the security forces.