The Pocatello Fire Department was investigating a possible chemical spill or leak Friday.
Emergency vehicles and personnel were on the 500 North block of Main Street at 4 p.m. and blocked traffic. The road reopened around 9:30 p.m. Residents were evacuated from the area as well.
Fire officials said Friday night, they didn't know what the substance is, but said it is extremely flammable. It smells like sewage.
The efforts of emergency responders were centered on a building that houses the Muse clothing store and some apartments.
Firefighters detected low oxygen levels in and around the building.
The owner of the building talked to Local News 8, saying the smell has been present in the building for some time, and she had called numerous agencies for help. The Owner says, fire officials we're called after a representative from Intermountain Gas Company did an inspection.
The investigation is continuing.