Dozens of Iraqi legislators walked out of parliament to protest parts of a draft law that would lay out rules for provincial elections later this year, marking another potential setback for US-backed proposals to ease Iraq's sectarian rifts. Radical Shi'ite cleric Muqtada al-Sadr, meanwhile, warned his fighters to stick with his cease-fire order after US and Iraqi raids Thursday in Baghdad's Sadr City, the main Shiite district and bastion of al-Sadr's Mahdi Army militia. Fifteen suspected militants were detained in the sweeps and one person was killed. The US military said troops targeted "criminal elements" responsible for attacks with mortars and powerful roadside bombs that the Pentagon links to Iranian aid. In parliament, Thursday's walkout postponed a planned vote on the measure on redistributing power in Iraq.