Explosive materials, including those used in the Boston Marathon bombing, were discovered at a Fayette County man’s home last month.

According to the Fayette County Sheriff’s Office, authorities launched an investigation into Trevor J. Satrom, 34, of Oran on Feb. 4. The investigation eventually grew to include the Bureau of Alcohol, Tobacco, Firearms and Explosives, the State Fire Marshal and the Iowa Division of Criminal Investigation.

Authorities said on Feb. 10, a search warrant was conducted at Satrom’s residence and bombmaking evidence was found. Officials recovered more than 30 pounds of black gunpowder, steel pipes threaded with drilled endcaps, two pressure cookers, fuse, BBs, shredded metal to be used as shrapnel, a working flamethrower capable of unleashing a 50-foot flame for more than a minute, napalm mix for the flamethrower, body armor, several guns, rifles and smoke grenades.

Satrom was hospitalized on Feb. 10 and released on March 4, authorities said. He was arrested the day of his release and charged with unlawful possession or storage of explosive material, a Class C felony punishable by up to 10 years in prison. As a result of further evidence testing, four counts of unlawful possession of offensive weapons were added to his list of charges. That offense is a Class D felony punishable by five years in prison.