(Reuters) – The U.S. Department of Justice on Thursday announced charges against three Iranians over allegations they stole information from aerospace and satellite technology firms on behalf of the Islamic republic’s Revolutionary Guards.

The indictments follow a flurry of recent actions against alleged Iranian cyber spies including the announcement, earlier on Thursday, that entities and individuals associated with an Iranian hacking group sometimes dubbed APT39 were being sanctioned by the Treasury Department.

U.S. Assistant Attorney General John Demers said in a statement it was the third time in three days that alleged Iranian hackers had been indicted, calling out what he described as “yet another effort by a rogue foreign nation to steal the fruits of this country’s hard work and expertise.”

The defendants, identified as Said Pourkarim Arabi, 34, Mohammad Reza Espargham, whose age is unknown, and Mohammad Bayati, 34, are alleged to have impersonated colleagues or academics to get their targets to download malicious software, prosecutors said.

Attempts to locate contact information for the Iranian defendants were not immediately successful. Messages sent to email addresses allegedly used by the hackers either bounced back as undeliverable or were not immediately returned.

At one point, according to prosecutors, Arabi, Espargham, and Bayati had a hit list more than 1,800 accounts long, including targets in the aerospace and satellite technology fields as well as employees of international governmental organizations. The indictment did not identify the people or organizations targeted but said they hailed from the United States, the United Kingdom, Australia, Israel, and Singapore.

Prosecutors said the trio were working for Iran’s Islamic Revolutionary Guard Corps, which the United States considers a terrorist organization. Arabi, the indictment says, was an IRGC operations manager and lived in IRGC housing.

A message left with Iran’s mission to the United Nations was not immediately returned. Tehran regularly denies involvement in hacking.

(Reporting by Raphael Satter; Editing by Tom Brown)

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