Federal authorities had warned Blackwater that its private security employees had committed violent acts against innocent Iraqi civilians long before a 2007 shooting incident that killed at least 14 people, according to a lawsuit filed Tuesday in Wake County…The suit contains new details about the Sept. 16, 2007, shootings in Nisoor Square in Baghdad…Blackwater…has said its men did nothing wrong…Now, the [plaintiffs’] attorneys are claiming that Blackwater…failed to take action earlier against its employees, before the Nisoor Square incident…The U.S. government warned the contractor about its workers' actions, but “Blackwater-Xe failed to take reasonable measures to address and curtail the unlawful and reckless conduct," the suit reads.