Iraqi security forces fired tear gas on Saturday to push back protesters who tried to remove blast walls erected on a bridge in central Baghdad to prevent anti-government rallies from reaching a heavily fortified government area, a day after violence claimed 42 lives. Initially, 30 were reported killed as Iraq was again engulfed in anti-government protests on Friday, but the death toll rose after a senior official said 12 protesters died in a fire they had started while storming the office of powerful militia during one of the rallies in the country’s south. The Interior Ministry and the Iraqi military issued statements Saturday saying some protesters have exploited the rallies and attacked government buildings and political party offices.