The New Nation - Internet Edition

Reuters, Basra

Explosions could be heard every 10 or 15 minutes in Basra, epicenter of an Iraqi government crackdown on followers of Shi'ite cleric Moqtada al-Sadr, on Thursday.

Authorities imposed curfews across southern Iraq in an effort to halt the spread of violence after the largest military offensive carried out by Iraqi forces without major backing from U.S. or British combat units.

More than 100 people have been killed and hundreds wounded in clashes which have divided Iraq's majority Shi'ite community and wrecked a ceasefire declared last year by Sadr.

Residents of Basra, Iraq's second largest city and main oil centre, have described the fighting as the worst since the U.S. invasion in 2003. Clashes have spread to the southern cities of Kut, Hilla, Diwaniya, Amara and Kerbala, as well as Shi'ite neighborhoods of Baghdad.

"We have been living for the last hours in hell. We have spent most of the time hiding under the staircase," said Basra resident Faris Hayder, 28. "We haven't seen anything like this since the foreign troops arrived in 2003."

Basra's police chief survived an assassination attempt overnight. A roadside bomb killed three of his bodyguards.

Hundreds of Sadr followers were gathering in Baghdad neighborhoods for demonstrations to demand the resignation of Prime Minister Nuri al-Maliki.

Sadr's aides say the ceasefire is still formally in place despite the fighting. He has called on his followers to stage a campaign of "civil disobedience," forcing schools, universities and shops to shut, and has threatened to declare a countrywide "civil revolt" if the two-day-old crackdown is not halted.

Ali Bustan, head of the health directorate for eastern Baghdad, said 39 bodies and more than 200 wounded had been brought to two hospitals in Sadr City, the vast Shi'ite slum named for Sadr's slain father and the cleric's main power base.

Mortar bombs, most apparently fired from the Sadr City area, have exploded across Baghdad for days. Mortars killed at least nine people on Tuesday and wounded dozens, including four inside the Green Zone fortified diplomatic and government compound.

Maliki, who has traveled to Basra to oversee the crackdown, has given the militants an ultimatum to surrender within three days or be declared outlaws. He has cancelled plans to attend an Arab summit in Damascus on Saturday.

U.S. and British assistance for the campaign in the south has been limited to air support and small teams of mentors.

Most of the Shi'ite areas where the fighting is taking place have virtually no foreign troops. The 160,000-strong U.S. force is mainly concentrated on Sunni and mixed areas near Baghdad and in the north. British troops who patrolled Basra pulled out of the city in December and are confined to an air base nearby.

With Washington planning to reduce its force by 20,000 over the next four months and U.S. Democratic presidential candidates calling for faster withdrawal from an unpopular war, the Iraqi government is under pressure to show it can impose its will.

The fighting exposes the deep divide within the Shi'ite community between the parties in Maliki's government who have control over the security forces and many southern governates, and Sadr's followers who in many Shi'ite areas rule the streets.