A Florida man convicted of setting off a pipe bomb in his backyard has been sentenced to a year in prison. 

Court records show that 61-year-old Joseph Caltagirone was sentenced Friday in Tampa federal court.  He pleaded guilty in December to possessing an unregistered destructive device. 

Tampa police say the bomb squad happened to be conducting training last April when they heard a loud explosion.  They followed a greyish-white smoke plume to Caltagirone's home, where they found PVC piping, hobby fuse, and chemicals commonly used to make explosives.  Investigators also reported finding a pipe bomb that contained an explosive mixture of Tannerite. 

A plea agreement says authorities found no evidence that Caltagirone intended to harm anyone.