Marines report 300 insurgents killed in Najaf

But CNN believes the numbers reported by al-Sadr.

Scott Baldauf, a reporter for The Christian Science Monitor who was in Najaf on Thursday, told CNN that the electric and water supplies to the city had been cut off and estimated that dozens of civilians were among the casualties in the violence.

"What we did see were civilian casualties at the main hospital in Najaf," Baldauf said. "Many of them had suffered bullet shot wounds and shrapnel as well."

Just because someone is being treated in a hospital does not make them a civilian:

Video obtained by Turkish network IHA showed fighters in Najaf, most of them dressed in civilian clothing, roaming the streets with rocket-propelled grenades.