March 15 (UPI) -- President Donald Trump's administration Thursday accused Russia of a concerted effort to hack the U.S. energy grid and other critical infrastructure.
The Department of Homeland Security and FBI released a joint Technical Alert stating hackers penetrated government entities and organizations in the energy, nuclear, commercial facilities, water, aviation, and critical manufacturing sectors.
"DHS and FBI characterize this activity as a multi-stage intrusion campaign by Russian government cyber actors who targeted small commercial facilities' networks where they staged malware, conducted spear phishing, and gained remote access into energy sector networks," the alert states.
The Russian cyber actors targeted the entities since at least March 2016 and conducted network reconnaissance, moved laterally, and collected information pertaining to Industrial Control Systems after gaining access.
Hackers used malware-infested documents and other means to target vendors and other companies affiliated with their main target before crossing over to gain access to higher-level networks to spy and collect information.
"The initial victims are peripheral organizations such as trusted third-party suppliers with less secure networks," the alert states. "The threat actors used the staging targets' networks as pivot points and malware repositories when targeting their final intended victims."
The alert follows a July 2017 report by officials at the FBI and Department of Homeland Security stating hackers had been targeting computer and security systems at nuclear facilities and manufacturing plants in the United States and elsewhere for two months.
It also comes as U.S. regulators announced new punitive sanctions against five Russian entities and 19 citizens for interfering in the United States' presidential election in 2016.