Iranian security forces are opening fire on protestors nationwide, according to a U.S.-based human rights group, reportedly killing hundreds of protestors and arresting thousands of others. The death toll from mass protests in Iran has risen to 544, according to data compiled by the U.S.-based Human Rights Activists News Agency on Sunday. ABC News cannot independently verify these numbers. The Iranian government has not provided any death tolls during the ongoing protests. #news #iran #tehran #p