A 23-year-old Russian in Milwaukee, the U.S. state of Wisconsin, who was accused by the FBI for controlling a network of infected computers that generated about one-third of the world's spam, is under arrest, according to a Thursday report of Milwaukee's Journal Sentinel.

Oleg Nikolaenko's activities had been tracked by Milwaukee FBI and Federal Trade Commission since 2007, according to a federal criminal complaint. He allegedly created a robot network, or " botnet," that investigators call Mega-D, to send out 10 billion unwanted e-mails a day with false return addresses. His clients included cyber hucksters who sell counterfeit goods or provide doubtful services.

Authorities found files like the malware that ran his robot network, called "botnet" in the Google mail records of the suspect.

Nikolaenko was arrested on Nov. 4 during his visit to Las Vegas. He is accused of violating the 2003 federal CAN-SPAM Act, which requires that businesses use accurate e-mail addresses and correctly identify the sender. He is scheduled to appear in federal court in Milwaukee on Friday.