BART detectives say Dennis McGuire recently took copper cable from BART property.
San Francisco police arrested McGuire in September after copper wiring was taken from an underground, electrical vault.
Thursday, BART police displayed some of the copper they found in McGuire's apartment.
They say there's been a spike in copper thefts from buildings, utilities, and transit systems across the country. That's because copper is worth a lot of money on the open market.