A Pembroke businessman pled guilty on Monday to federal charges of hiring illegal aliens at the New Bedford company at which he was president and principal shareholder.

Francesco Insolia, 51, of Pembroke pled guilty to helping harbor and conceal aliens by allowing the company, Michael Bianco Inc., to submit false Social Security numbers for employees, according to a release from U.S. Attorney Michael J. Sullivan. The charges stem from an investigation that culminated in a March 6, 2007 raid on the company’s offices, in which about 361 illegal aliens were detained.

Started by Insolia in 1985, Michael Bianco Inc. manufactures handbags and other fine leather goods and won several Department of Defense contracts worth about $230 million between 2001 and 2006, according to Sullivan. Because of those military contracts, the company’s workforce grew from about 85 people in 2001 to about 650 in 2006.

Insolia and Michael Bianco Inc. both pled guilty to the federal charges on Nov. 3. The company’s production manager, Dilia Costa, and contracts administrator, Gloria Melo, pled guilty to other charges on Oct. 24.

Insolia will serve up to 18 months in prison and pay a fine of $30,000. The company will pay a fine of $1.5 million and will pay about $460,000 in restitution for the overtime owed to employees, according to Sullivan.