The joint alert from the FBI and DHS, first reported by Reuters on June 30, said the hackers have been targeting the industry since at least May. Several days earlier, E & E News, an energy trade publication, had reported that U.S. authorities were investigating cyber-intrusions affecting multiple nuclear-power-generation sites. The malicious activity comes as President Trump and Russian President Vladimir Putin on Friday acknowledged “the challenges of cyberthreats” and “agreed to explore creating a framework” to better deal with them, including those that harm critical infrastructure such as nuclear energy, according to Secretary of State Rex Tillerson in remarks to reporters. On Saturday, Putin told reporters that he and Trump agreed to set up a working group “on the subject of jointly controlling security in cyberspace.”