The United States on Friday (local time) charged and sanctioned nine Iranians and an Iranian company for attempting to hack into hundreds of universities worldwide, dozens of companies and parts of the US government, including its main energy regulator, on behalf of Tehran's government.
The cyber attacks, beginning in at least 2013, pilfered more than 31 terabytes of academic data and intellectual property from 144 US universities and 176 universities in 21 other countries, the US Department of Justice said, describing the campaign as one of the largest state-sponsored hacks ever prosecuted.
The US Treasury Department said that it was placing sanctions on the nine people and the Mabna Institute, a company US prosecutors characterised as designed to help Iranian research organisations steal information.
US Deputy Attorney General Rod Rosenstein said the nine Iranians were considered fugitives who may face extradition in more than 100 countries if they travel outside of Iran.
Authorities "will aggressively investigate and prosecute hostile actors who attempt to profit from America's ideas by infiltrating our computer systems and stealing intellectual property", Mr Rosenstein said at a news conference.
He said the case "will disrupt the defendants' hacking operations and deter similar crimes".
The hackers were not accused of being directly employed by Iran's government. They were instead charged with criminal conduct waged primarily through the Mabna Institute on behalf of the Islamic Revolutionary Guard Corps, the elite military force assigned to defend Iran's Shi'ite theocracy from internal and external threats.
There was no immediate response to the charges and sanctions in Iran's state-run media.
The targeting of the Federal Energy Regulatory Commission, or FERC, was especially concerning, US Attorney Geoffrey Berman said, because it oversees the interstate regulation of energy in the United States and holds details of some of the country's "most sensitive infrastructure".
Hackers targeted email accounts of more than 100,000 professors worldwide, half located in the United States, and compromised about 8,000 of them, prosecutors said. Hackers also targeted the US Labor Department, the United Nations and the computer systems of the US states Hawaii and Indiana, prosecutors said.
Friday's actions are part of an effort by senior cyber security officials at the White House and across the US government to blame foreign countries for malicious hacks.
They were announced a day after US President Donald Trump named John Bolton, a former US ambassador to the United Nations who is deeply sceptical of the 2015 international nuclear accord with Iran, as his new national security adviser. Mr Trump himself has repeatedly cast doubt on the nuclear deal, in which the US and other world powers eased sanctions in exchange for Tehran putting limits on its nuclear program.