WASHINGTON (AP) — Four Russian officials, including hackers with a government intelligence agency, have been charged with the malicious hacking of critical infrastructure around the globe including the U.S. energy and aviation sectors between 2012 and 2018, the U.S. Justice Department and British Foreign Office announced.

Among the thousands of computers targeted in some 135 countries were machines at a Kansas nuclear power plant — whose business network was compromised — and at a Saudi petro-chemical plant in 2017 where the hackers overrode safety controls, officials said Thursday.

Though the intrusions date back years, the indictments were unsealed as the FBI has raised fresh alarms about efforts by Russian hackers to scan the networks of U.S. energy firms for vulnerabilities that could be exploited during Russia’s war against Ukraine.

The Foreign Office suggested in an announcement on its website that the timing — exposing “the global scope” of hacking by the KGB’s successor spy agency — was directly related to Russian President Vladimir Putin’s “unprovoked and illegal war in Ukraine.”

Additionally, multiple U.S. federal agencies on Thursday published a joint advisory on the hacking campaign, alerting energy executives to take steps to protect their systems from Russian operatives.

“The DOJ is firing warning shots at people who run Russia’s cyberattack capability,” tweeted threat intelligence analyst John Hultquist at the cybersecurity firm Mandiant.

“Russian state-sponsored hackers pose a serious and persistent threat to critical infrastructure both in the United States and around the world,” Deputy Attorney General Lisa Monaco said in a statement. “Although the criminal charges unsealed today reflect past activity, they make crystal clear the urgent ongoing need for American businesses to harden their defenses and remain vigilant.”

None of the four defendants is in custody, though a Justice Department official who briefed reporters said officials deemed it better to make the investigation public rather than wait for the “distant possibility” of arrests. The State Department on Thursday announced rewards of up to $10 million for information leading to the “identification or location” of any of the four defendants.

The indicted Russians include an employee at a Russian military research institute accused of working with co-conspirators in 2017 to hack the systems of a foreign refinery and to install malicious software, twice resulting in emergency shutdowns of operations. The British Foreign Office identified the target as Saudi and said the military research institute was being sanctioned. The so-called “Triton” case — affecting the Petro Rabigh complex on the Red Sea — has been well-documented by cybersecurity researchers as one of the most dangerous on record. The malware was designed with a goal of inflicting physical damage by disabling a safety shutdown function that would normally stop a refinery from “catastrophic failure,” a Justice Department official said.

The employee, Evgeny Viktorovich Gladkikh, also tried to break into the computers of an unidentified U.S. company that operates multiple oil refineries, according to an indictment that was filed in June 2021 and was unsealed Thursday.

The three other defendants are alleged hackers with Russia’s Federal Security Service, or FSB — which conducts domestic intelligence and counterintelligence — and members of a hacking unit known to cybersecurity researchers as Dragonfly.

The hackers are accused of installing malware into legitimate software updates on more than 17,000 devices in the U.S. and other countries. Their supply chain attacks between 2012 and 2014 targeted oil and gas firms, nuclear power plants and utility and power transmission companies, prosecutors said.

The goal, according to the indictment, was to “establish and maintain surreptitious unauthorized access to networks, computers, and devices of companies and other entities in the energy sector.” That access would enable the Russian government to alter and damage systems if it wanted to, the indictment said.

A second phase of the attack, officials said, involved spear-phishing attacks targeting more than 500 U.S. and international companies, as well as U.S. government agencies including the Nuclear Regulatory Commission.

The hackers also successfully compromised the business network — though not the control systems — of the Wolf Creek Nuclear Operating Corporation in Burlington, Kansas, which operates a nuclear power plant.

The British Foreign Office said the FSB hackers had also targeted U.K. energy companies and stolen data from the U.S. aviation sector and other key U.S. targets.

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AP reporter Frank Bajak contributed from Lima, Peru. Follow Eric Tucker on Twitter at http://www.twitter.com/etuckerAP.

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