Gun powder and carbon dioxide canisters were being converted into improvised explosive devices by a convicted felon at his residence, according to the Warren County Sheriff’s Department.

Kenneth L. Simpson, 29, Warrenton, is now facing two charges of manufacturing an illegal weapon. The Class D felony has a maximum prison sentence of seven years if he is convicted.

He also faces charges of unlawful possession of a firearm and felony drug possession.

Deputies had received complaints of large explosions in the last few months around the Simpson residence on Shetland Lane northwest of Innsbrook, according to the sheriff’s department. Missouri State Highway Patrol bomb squad members and a sheriff’s deputy went to Simpson’s residence Sept. 13 and located the materials for the explosives, according to a report.

Simpson allegedly admitted to making and detonating the explosives.

Bullet shell casings found on the property also led an investigator to ask if Simpson possessed any firearms. Simpson was convicted on felony property damage and motor vehicle tampering charges in 2006, and therefore is not allowed to possess any firearms.

During the execution of a search warrant, a 9mm semi-automatic handgun was located in Simpson’s residence, as was a pipe that tested positive for the presence of methamphetamine.

Simpson is now being held in the Warren County Jail in lieu of a $20,000 bond. He has an arraignment scheduled for Sept. 27 at the Warren County Circuit Court.