Pollard was then moved from FCC Petersburg in Virginia, where he had been held since 1986, to a federal prison hospital in Springfield, Missouri, to undergo a battery of mental health tests. In June 1988, he was transferred to the federal maximum security prison in Marion, Illinois, and in 1993 to FCI Butner Medium at the Butner Federal Correction Complex in North Carolina. In May 1991, Pollard asked Avi Weiss to be his personal rabbi. Israeli Chief Rabbi Mordechai Eliyahu was also a supporter of Pollard, and campaigned for his release from prison.