NEW HAVEN, Conn. (AP) -- Federal authorities are asking for the public's help in tracking down a man they say helped run one of the largest online child pornography websites ever investigated by law enforcement.

Homeland Security Investigations says the suspect, whose real first name may be Shaun, may live within a 100-mile radius of New Haven, Connecticut.

Police say he is between 40 and 50 years old, likely works in construction management and travels regularly. Police think he has degrees in electrical engineering and construction management and is proficient with computer programming. He may have previously worked in IT. He may have family living in Hamburg, Germany.

He is the only remaining suspected administrator of the website investigated as part of Operation Round Table, one of the largest online child exploitation investigations in history.