A Polish and Algerian journalist were shot dead in their car by gunmen in the Mahmoudiyah region south of Baghdad today.
A second Pole was wounded in the attack.
The region lies on the routes heading from the capital to Najaf and other southern cities and has been the scene of frequent gun attacks on the roads. An American missionary and two CNN employees were killed in February and January in the same area.
In Karbala, US troops skirmished with militiamen loyal to anti-US cleric Muqtada al-Sadr, witnesses said. The exchange began when a roadside bomb hit a US patrol, damaging three vehicles, prompting a clash between gunmen and troops, the witnesses said.
Al-Sadr's al-Mahdi Army militia was out in force in Kufa and Najaf today, fearing a US assault to capture al-Sadr could be imminent. Militiamen and US troops had a fierce mortar exchange overnight.
Fighters - draped with ammunition belts and carrying automatic weapons and rocket-propelled grenade launchers - moved around the streets of the two cities in large numbers and took positions behind earthen mounds and behind buildings.