Iraqi Prime Minister Nouri al-Maliki says he will continue the Iraqi military offensive in Basra "to the end" with no negotiations or retreat, despite angry protests in Shi'ite districts calling for his resignation. VOA Correspondent Challiss McDonough has been monitoring events from our Middle East Bureau in Cairo and reports intense fighting in Basra continued for a third day.

Tens of thousands of supporters of Shi'ite cleric Moqtada al-Sadr took to the streets of Baghdad to protest the Iraqi military crackdown on Shi'ite militias in the southern city of Basra. Huge demonstrations were held in several districts of the capital, including the sprawling slum of Sadr City, a stronghold of Sadr's militia, the Mahdi Army.

Protesters chanted slogans denouncing Prime Minister Nouri Al-Maliki and demanding his resignation.

Prime Minster Maliki vowed he will "never back off" from his promise to rid Basra of what he called "criminals and gunmen." The prime minister, who is in Basra to supervise the military operation, has given the militants until Friday to surrender their weapons.

Many businesses and shops in the Shi'ite districts of Baghdad have stayed closed since al-Sadr called for a general strike to protest the offensive.

Officials from al-Sadr's political movement say they feel the government is targeting them, and most of the fighting has taken place in districts controlled by Mahdi Army fighters.

Iraqi officials have insisted the offensive is not targeting the al-Sadr political organization, only what they term "outlaws" and "criminal groups" who they say are operating "under the banner" of the Mahdi Army, but are not really loyal to the cleric.

Iraqi and U.S. officials have downplayed concerns the fighting in Basra threatens to wreck a ceasefire that had been in place between Sadr loyalists and rival Shi'ite groups that control much of Iraq's security forces. U.S. military officials have said the al-Sadr ceasefire is a key factor behind the reduction of violence in Iraq during the past year.

Speaking in Ohio, President Bush said the Basra offensive is a sign of the progress Iraqi security forces have made.

"This offensive builds on the security gains of the surge and demonstrates to the Iraqi people that their government is committed to protecting them. There is a strong commitment by the central government of Iraq to say that no one is above the law."

Meanwhile, fighting rocked Basra for a third straight day. Gunbattles also erupted in the southern city of Kut, while curfews remained in effect elsewhere in the south.

A bomb explosion damaged one of the two main oil pipelines from Basra, disrupting oil exports from southern Iraq for the first time since 2004.

A spokesman for Iraq's Southern Oil Company said the attack would cut crude exports from Basra by about a third. But Iraqi government officials in Baghdad told the Reuters news agency the damage was not serious and could be repaired quickly.

In Baghdad, barrages of rocket and mortar fire slammed into the heavily-fortified Green Zone government and diplomatic compound. The U.S. embassy in Baghdad said a U.S. government employee was killed in the Green Zone attacks that officials say appeared to originate in Shi'ite neighborhoods.