Arbaeen marks the end of 40 days of mourning after the anniversary of the death of Imam Hussein, the Prophet Mohammad's grandson who was killed at the battle of Karbala in 680 A.D.

The latest attacks also came amid continuing anti-government demonstrations in several Sunni-dominated cities protesting against marginalization by the Shiite-led government as well as the alleged arrest of hundreds of Sunnis.

The demonstrators also accused the Shiite-dominated security forces of arresting women instead of the wanted male of their family members.

The protests were first sparked last week after the Iraqi security forces arrested chief of the Sunni Finance Minister Rafia al-Issawi's protection force and nine bodyguards over charges of terrorism.

At the end of last year, an arrest warrant was issued against the Sunni Vice President Tariq al-Hashimi on charges of running death squad and dozens of his bodyguards were arrested.

Soon after the U.S. troops fully withdrew from Iraq late last year, Iraq plunged into serious political row as Maliki sought to arrest his political rival Hashimi, a leading member of the Sunni- backed Iraqia bloc, over terror charges.