BASRA, Iraq (Reuters) - Protesters in Iraq's Basra on Thursday set fire to the headquarters of the ruling Dawa Party, the Islamic Supreme Council and the largest Iran-backed Shi'ite militia group in the country, the Badr Organization, local security sources said.

They also attacked the local offices of the state-run al-Iraqiya TV channel, in the fourth consecutive night of violent unrest.

(Reporting by Aref Mohammed; writing by Raya Jalabi; Editing by Toby Chopra)