German police are investigating after an angry man returned a computer he had just bought saying it was packed with small potatoes instead of computer parts. The store replaced the computer free of charge but became suspicious when he returned a short time later with another potato-filled computer casing, police in the western city of Kaiserslautern said Monday. "The second time he said he didn't need a computer any more and asked for his money back in cash," a police spokesman said. Police are now investigating the man for fraud.