A 53 year-old Gilroy man may face criminal charges in connection with the explosive device he was building, that reportedly blew up his hand on Monday. Reportedly, it’s unknown if the man was making homemade fireworks, or something more serious when the explosion occurred around 2:30 p-m on the 17-hundred block of Mantelli Drive. The explosion took place in a shed behind the home where the man and his elderly mother live.