A judge says the U.S. Parole Commission will have to explain the reasons it wants to monitor computer use and trace the whereabouts of convicted spy Jonathan Pollard.

Judge Katherine Forrest said at a hearing Monday in Manhattan federal court that a one-page explanation issued so far is insufficient. She said she wants to know whether Pollard still possesses top-secret information that could endanger national security.

Pollard's defense lawyers say information he possessed before he served 30 years in prison is of no value. They say strict monitoring and a curfew are unreasonable.

Assistant U.S. Attorney Rebecca Tinio says the Justice Department's National Security Division says the majority of information Pollard once had remains classified.

Pollard was released from prison last month. He is planning to work in finance.