The US Department of Justice on Thursday announced charges against three Iranians accused of stealing information from aerospace and satellite technology companies for Iran’s Islamic Revolutionary Guard Corps.
The indictments follow several recent actions against alleged Iranian cyber spies.
They included the announcement earlier on Thursday that entities and people associated with an Iranian hacking group called APT39 had sanctions imposed on them by the Treasury Department.
US assistant attorney general John Demers said it was the third time in three days that Iranians had been indicted over hacking.
Mr Demers called it "yet another effort by a rogue foreign nation to steal the fruits of this country's hard work and expertise".
Said Pourkarim Arabi, 34, Mohammad Reza Espargham, whose age is unknown, and Mohammad Bayati, 34, are accused of impersonating colleagues or academics to have their targets download malicious software, prosecutors said.
Messages sent to email addresses used by the hackers bounced back as undeliverable or were not immediately returned.
At one point, prosecutors said, Arabi, Espargham, and Bayati had a list of more than 1,800 accounts, including some in aerospace and satellite technology fields and of employees of international government organisations.
The indictment did not identify the people or organisations targeted but said they were in the US, UK, Australia, Israel and Singapore.
Prosecutors said the trio were working for the IRGC, which the US considers to be a terrorist organisation.
Arabi, the indictment says, was an IRGC operations manager and lived in housing owned by the corps.
Tehran regularly denies involvement in hacking.