The FBI arrested a Norwalk man Friday and charged him with trading stock on insider financial information about Harman International Industries where he worked, with the Department of Justice pursuing a criminal complaint in tandem with civil charges filed by the Securities and Exchange Commission. Norwalk resident Dennis W. Hamilton , 45, was released on a $2 million bond after appearing in New Haven before U.S. Magistrate Judge Sarah Merriam , according to the office of Deirdre Daly , U.S. Attorney for the District of Connecticut, which said Harman has cooperated in the investigation.