WASHINGTON — U.S. intelligence agencies are “urgently warning” private-sector companies nationwide that Iranian actors are conducting cyber operations targeting critical U.S. infrastructure, a campaign that has already caused disruptions, according to a government notice. The activity comes as President Trump threatened Iran’s infrastructure, particularly its bridges and power plants. Iran’s attack targeted products by Rockwell Automation’s Allen-Bradley, one of the most widely used industrial automation brands, according to the notice, which was first reported Tuesday by The Times. The advisory said that cyber actors affiliated with Iran were exploiting “programmable logic controllers across U.S. critical infrastructure.” Tehran’s targeting campaigns against U.S. organizations “have recently escalated, likely in response to hostilities between Iran and the United States and Israel,” the notice added. The advisory was issued Tuesday jointly by the FBI, the Cybersecurity and Infrastructure Security Agency, the National Security Agency, the Environmental Protection Agency, the Department of Energy and Cyber Command. In its own notice, the EPA warned that Iran’s cyberattack had already disrupted “commonly used operational technology at drinking water and wastewater systems,” and that the …