Convicted serial burglar and robber Mark T. Missino added another criminal charge to his rap sheet Thursday when he pleaded guilty in U.S. District Court in Bridgeport to possession of firearms by a previously convicted felon.

Missino, 46, formerly of Waterford, and his partner Bernard McAllister of Lisbon, were found in possession of 19 guns they stole during a string of residential burglaries that took place between 2008 and 2010, according to the U.S. Attorney’s office. The firearms were discovered in an East Lyme storage locker with more than 8,000 other items believed to have been taken during the burglaries.

Missino had previously been convicted of multiple felony offenses in Connecticut and Florida, including larceny, burglary, robbery, grand theft and escape. He is scheduled to be sentenced April 24 by U.S. District Judge Stefan R. Underhill and is subject to the Armed Career Criminal Act, a federal law imposing severe penalties for firearm or ammunition possession by persons who have been convicted of at least three violent felonies or serious drug offenses. He faces 15 years to life in prison.

Missino also faces a 25-year prison sentence for state offenses, including dozens of burglaries throughout Connecticut and a home invasion/robbery involving Grader Jewelers in Norwich.

McAllister, 43, formerly of Lisbon pleaded guilty to the federal firearms charge on June 6, 2013, and awaits sentencing.

The case was investigated by the Bureau of Alcohol, Tobacco, Firearms and Explosives, the Connecticut State Police, the Massachusetts State Police, and the East Lyme, Greenwich, Madison, Guilford, Glastonbury, North Branford and Wallingford police departments. The case is being prosecuted by Assistant U.S. Attorneys Jonathan S. Freimann and Robert M. Spector.