The Justice Department says it is working to dismantle a global computer network that sent hundreds of millions of spam emails worldwide each year.
The Monday announcement comes after a Russian man alleged to be at the head of the so-called Kelihos botnet scheme was detained in Spain at the request of U.S. authorities. A criminal case against Pyotr Levashov remains sealed.
A civil complaint filed in U.S. court seeks to stop Levashov from continuing the scheme and calls him "one of the world's most notorious criminal spammers."
Authorities say Kelihos botnet also harvested login credentials and installed ransomware and other malicious software.
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