Mehdi Army fighters remain in control in areas of Basra
US President George W Bush has called the Iraqi government offensive against militiamen in Basra "a defining moment in the history of a free Iraq".
Iraqi Prime Minister Nouri Maliki has set a deadline for the Mehdi Army, which still controls large parts of the city, to lay down their arms for money.
Correspondents say the militia has so far ignored the ultimatum.
More than 130 people have been killed and 350 injured since a clampdown on militias began in Basra on Tuesday. http://news.bbc.co.uk/1/hi/world/middle_east/7319678.stm