A South Portland man was arrested Wednesday after police found a suspicious substance at his home.

Police and a SWAT Team executed a search warrant at a home on Florence Street on Wednesday, with detectives uncovering black powder and an unidentified substance.

Residents of nearby homes were evacuated as a precaution.

Police arrested 40-year-old John Flumerfelt, who’s been charged with criminal use of explosives and may face firearm-related charges.

Police said there’s no ongoing threat to the public.