A federal grand jury has indicted two Iranian nationals for a massive ransomware attack against the city of Atlanta, Ga., earlier this year, the Department of Justice reported this week.

From around March 10 until March 22, Faramarz Shahi Savandi and Mohammed Mehdi Shah Mansouri executed a ransomware attack on Atlanta. They used SamSam ransomware to encrypt about 3,789 computers, servers, and workstations belonging to the city, and demanded .8 Bitcoin to decrypt each machine – or six Bitcoin to decrypt them all.

A ransom note instructed the city to access a Bitcoin address to pay the ransom, providing a domain only reachable on the Tor browser. In the days following the attack, the Web page containing the decryption key was inaccessible and Atlanta did not submit a ransom payment.

The attack "significantly disrupted" Atlanta's operations, interfered with governmental processes, and caused millions of dollars in losses, officials say. The attackers have been charged with intentional damage to protected computers located in Atlanta that caused losses exceeding $5,000, affected 10-plus protected devices, and threatened public health and safety.

They are also charged in the US District Court for the District of New Jersey, where they face charges including one count of conspiracy to commit wire fraud, one count of conspiracy to commit fraud and related activity in connection with computers, and two substantive counts of intentional damage to a protected computer located in New Jersey.

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