Russian government-linked hackers have targeted the U.S. energy industry and other sectors critical to running the economy in a new surge of online attacks since at least March 2016, federal agencies said on Thursday.

The hacking campaign, orchestrated by a seven-year-old group known as Dragonfly, has hit U.S. government entities and domestic companies in the energy, nuclear, commercial facilities, water, aviation and critical manufacturing sectors, according to an alert the U.S. Computer Emergency Readiness Team put out on Thursday.

“In multiple instances, the threat actors accessed workstations and servers on a corporate network that contained data output from control systems within energy generation facilities,” the U.S. CERT said. [read more]