LOS ANGELES, Nov. 9 (Xinhua) -- A Los Angeles computer security consultant agreed Friday to plead guilty to using computer spyware that he planted in other people's computers to steal identities, U.S. federal prosecutors said.

    John Schiefer, 26, was accused of using "botnets" -- armies of infected computers -- to steal the identities of victims across the country by extracting information from their personal computers and wiretapping their communications, according to the U.S. Attorney's Office here.

    This is the first time someone in the United States has been charged under the federal wiretap statute for conduct related to botnets, prosecutors said.

    Court documents outline a series of schemes in which Schiefer and several associates developed and distributed a malicious computer code to vulnerable computers.

    Schiefer and the others used the illicitly installed code to assemble armies of up to 250,000 infected computers, which they used to engage in a variety of identity theft schemes.

    In his plea agreement, Schiefer acknowledged installing the malicious computer code, or "malware," that acted as a wiretap on compromised computers, prosecutors said.

    The victims, unaware their computers had been infected, continued to use their computers to engage in commercial activities.

    Schiefer used the malware to intercept electronic communications being sent online from those computers to Pay Pal and other financial service websites.

    Once in possession of the intercepted communications, Schiefer sifted through the data to mine usernames and passwords, accessing bank accounts to make purchases without the consent of the true owners, according to prosecutors.

    Schiefer also admitted that he transferred both the wiretapped communications and the stolen PayPal information to others.

    In another scheme, Schiefer installed malware on infected computers running Microsoft operating systems, causing them to disgorge usernames and passwords from a secure storage area known as the PStore, and used such data to access victims' bank accounts.

    Schiefer's initial appearance in federal court is set for November 28. He faces a maximum sentence of 60 years in federal prison and a 1.75-million-dollar fine.