DETROIT -

A Trenton man has been sentenced to nine years in prison for possessing explosives and making bombs.

John Robert Kennedy, 43, formerly of St. Joe, Indiana, was sentenced to 108 months in prison by United States District Judge John Corbett O'Meara and ordered to pay a $20,000 fine.

Kennedy was convicted following a three-week jury trial of on charges of possession of a destructive device, felon in possession of a destructive device and manufacture of a destructive device. Prior to trial, he pleaded guilty to being a felon in possession of ammunition and explosives.

On April 28, 2011, Kennedy, disguising his voice in a foreign accent, made a telephonic bomb threat to Trenton High School.

He threatened that four bombs would be detonated in the school within the hour. The school was evacuated and searched. Later that evening a device was found in the parking lot area of the school by a teacher.

On April 29, 2011, Kennedy detonated another device in the parking lot of an ACO hardware store in Trenton. Remnants of a destructive device were found and were determined by forensic experts to contain explosive materials. Kennedy was identified as the suspect who placed the devices through the use of a Crime Stoppers announcement.

Kennedy was previously convicted of similar criminal charges involving explosives and has been in custody since July 2011.

The case was prosecuted by Assistant United States Attorney Susan Gillooly with the assistance of ATF, Detroit Field Division and the Trenton Police Department.