Hours after the mosque bombing, an explosives-laden ambulance ripped through a wedding party near the rebel bastion of Mahmudiyah, south of Baghdad, killing six and wounding at least 42 people, police said.

In the first attack, a car exploded outside the al-Taf mosque in south-western Baghdad, where Shi’ites were celebrating one of Islam’s most important holidays, the Eid al-Adha, or Feast of Sacrifice, which coincides with the yearly pilgrimage to Mecca in Saudi Arabia.

Casualties from the blast, including women and children, were rushed to a nearby hospital.

It is the second attack on a Shi’ite mosque in Baghdad this week.

One of a series of car bombs that hit the capital on Wednesday exploded near a Shi’ite mosque just before noon prayers. No worshippers were hurt in that blast.

Militant leader Abu Musab al-Zarqawi is thought to be behind an audio tape on which a voice warned of attacks targeting US forces to continue for years.

A top Iraqi police official said intelligence sources estimate 150 car bombs and 250 suicide bombers are preparing to strike in coming days, according to a CNN report.

The official said the information was garnered through interrogations of recently-captured insurgents.

Targets are expected to be election centres and other locations.

Insurgents are determined to derail January 30 elections, expected to be dominated by Iraq’s long-oppressed Shi’ite majority, and several attacks have been launched on Shi’ite shrines and political offices.

Two car bombs have targeted the Baghdad offices of the Supreme Council for the Islamic Revolution in Iraq (SCRIRI), the headlining Shi’ite party, in two months.

Iraqi officials and Shi’ite leaders have blamed the attacks on Sunni militants.