Iraqi officials say an attack by insurgents has left much of Baghdad without water, as temperatures reached 40 degrees Celsius.
Officials said Friday insurgents sabotaged a pumping plant near the city. They say the damage could take several days to repair.
Iraqis complain about frequent water and fuel shortages and power cuts as officials struggle to repair the damaged infrastructure with limited funds.
Friday gunmen in central Baghdad have killed a prominent Shi'ite cleric linked to spiritual leader Grand Ayatollah Ali al-Sistani.
Kamal Ezz al-Din al-Ghuraifi and two bodyguards were killed Friday outside a mosque in a drive-by shooting. Shi'ite officials say the cleric was
Ayatollah al-Sistani's representative in the Iraqi capital.
Earlier Friday in Baghdad, a suicide car bomber killed a bystander outside party offices for Iraqi Prime Minister Ibrahim al-Jaafari, who is also a Shi'ite.
Iraqi officials said the bomb detonated near the political offices of the Islamic Dawa party in Baghdad's Mansour neighborhood.
They say the prime minister was not in the office, which used to be his residence, when the explosion occurred.
In other developments, coalition forces say they have uncovered a huge cache of weapons in the northern city of Kirkuk, following a tip from an Iraqi civilian.
A statement Friday from the U.S.-led coalition said the cache included artillery rounds and high explosives, which it said are the key components of car and roadside bombs. The statement praised the Iraqi army, police and civilians for their help in locating and securing the weapons cache.
The commander of the Multinational Force in Iraq, Major General David Rodriguez, said in Baghdad Friday that Iraqis are making what he called "steady progress" against the insurgency. He noted that the presence of Iraqi soldiers has boosted civilian confidence, and led to a significant increase in tips.