The United States intensified its actions against Iran on Tuesday, imposing sanctions on four individuals and two companies accused of conducting cyber-attacks for the Iranian military.

According to the US Treasury Department, these entities were involved in "malicious cyber-activity" to the benefit of Iran's Islamic Revolutionary Guards Corps' Cyber-Electronic Command (IRGC-CEC).

“Iranian malicious cyber actors continue to target US companies and government entities in a coordinated, multi-pronged campaign intended to destabilize our critical infrastructure and cause harm to our citizens,” said Under Secretary of the Treasury for Terrorism and Financial Intelligence Brian E. Nelson.

State Department spokesman Matthew Miller also said in a statement that Washington “will not tolerate malicious cyber activities victimizing US companies”.

In a parallel move, the US Justice Department and the FBI unsealed an indictment against the four individuals, accusing them of participating in a coordinated hacking initiative starting around 2016 through April 2021. Attorney General Merrick Garland highlighted the extensive nature of the cyber operations directed at American firms and crucial government departments.

The Treasury's statement emphasized the role of the IRGC-CEC in orchestrating the cyber offenses through a network of front companies. One such company, Mehrsam Andisheh Saz Nik, was among those sanctioned. The Treasury underscored that many in Iran might not realize these companies are fronts used to support the military's cyber operations.

The sanctions imposed will freeze any US assets held by the implicated parties and prohibit any transactions between them and US citizens, effectively cutting them off from the American financial system.

Last week, the US and UK unveiled comprehensive sanctions targeting Iran's drone program, in response to Iran's missile and drone strikes on Israel earlier this month.