BAGHDAD, June 10: The first heavy fighting between Iraqi police and Shia leader Moqtada Sadr's militia killed six people on Thursday after a UN resolution failed to end diplomatic discord over Iraq or brewing ethnic tension in the country.

After battling US troops for two months, Moqtada Sadr's Mehdi Army turned on local police in Najaf as they began rounding up militia in the streets and threatened to evict them from the Imam Ali Mosque.

Najaf General Hospital administrator Ali Moqtada Mohsen said a police official and a civilian were killed and 24 people wounded in shooting that began and could still be heard in the city by late Thursday morning. Police began patrolling the streets of Najaf last Friday as a truce between the Mehdi Army and US troops finally took after fighting killed hundreds of militia.

The deal saw Moqtada Sadr's men agree to withdraw from Najaf and the adjacent town of Kufa, which they seized in April as part of a bigger uprising across central and southern Iraq. But they have clung to positions around the mosque and the city's cemetery, drawing a warning earlier this week from police chief to leave or face fire.

UN RESOLUTION: The clashes came as tension rose between the Shias and Kurds over Tuesday's UN resolution on Iraq, which spells out the country's legal and political framework after the return of sovereignty on June 30.