Baghdad - A suicide bomb blast on Sunday killed at least 40 people and wounded 79 in the Kadhimiya area of northern Baghdad, with most of the victims Iranian pilgrims, the Voices of Iraq news agency reported, citing a security source.

The agency said the attack was carried out by a female suicide bomber. The woman wearing an explosives belt blew herself up at a joint army-police checkpoint in the Kadhimiya area, the source told the agency.

According to the source, most of the casualties were Iranian pilgrims who were among the many foreigners who had come to commemorate the Shiite festival of Ashoura at the shrine of Imam Musa al-Kadhim, in the Baghdad district bearing his name.

The attacker had seemingly intended to detonate the explosives amid the crowds at the shrine.

The 10-day ritual of Ashoura culminates with the mourning of the martyrdom of Imam Hussein Ibn Ali at the battle of Karbala.

Shiite pilgrims have been a repeated target of extremist Sunni Muslim groups operating in Iraq, during their annual celebrations of religious events.

US and Iraqi authorities say al-Qaeda militants have increasingly relied on women to conduct suicide attacks, as they can better evade security searches and their clothing helps them to conceal explosive belts and vests. (dpa)