A post office supervisor was busted for selling thousands of dollars worth of baseball and sports trading cards that had been stolen from the mail, according to a statement from the United States Attorney for the Southern District of New York.

John Bu, a customer service supervisor at the Brooklyn Processing and Distribution Center in East New York, allegedly purchased the collectable cards from his supervisor, who was also arrested, according to the criminal complaint. The cards included famous names like Mickey Mantle and Albert Pujols.

He allegedly sold the cards for $6,250 to a store in Westchester in November 2013, according to court records.

Bu allegedly told investigators that he in fact purchased about $7,000 worth cards and coins in 2008 and 2009, including cards of Mantle, Jackie Robinson and Lou Gehrig, from his supervisor at the time. He allegedly admitted that he "assumed" the cards were stolen, according to the complaint.

Bu, who became a supervisor in 2007, was charged with possessing stolen mail, according to the complaint. He was arraigned Thursday in White Plains federal court and released on a $25,000 bond, said a spokesman for the U.S. Attorney's office in the Southern District of New York.