Shia militia grabbed six Sunnis, doused them with kerosene and burned them alive Friday in what is believedto be revenge for deadly car bombings and mortar attacks in Baghdad's largest Shia district.

Police Capt. Jamil Hussein said Iraqi soldiers did not intervene while the Sunnis were being attacked as they left Friday worship services.

The killings occurred as members of the Mahdi Army militia burned four mosques and several homes while killing an unknown number of Sunni residents in the once mixed Hurriyah neighbourhood of Baghdad.

Baghdad is under a 24-hour curfew aimed at stopping widespread sectarian violence in the wake ofThursday's car bombings and mortar attacks by Sunni Muslim insurgents in the Shia Sadr City slum.

On Friday, funeral processions began for the peoplekilled in the attack. Iraqi Prime Minister Nouri al-Maliki, himself a Shia, ordered police to guard the processions carrying victims to Najaf, the holy Shia city where they will be buried.

Sunni insurgents blew up five car bombs and fired mortars in Sadr City, killing at least 215 people and wounding 252 in a dramatic attack that sent the U.S. ambassador racing to meet with Iraqi leadersin an effortto contain the growing sectarian war.

With files from the Associated Press