Nelson police are investigating in connection with the evacuation of a downtown property Monday.
The home on the corner of Vernon and Cedar needed a fire department hazmat team to deal with nitric acid found on scene.
The occupants had reported feeling unwell in the building.
Sergeant Dino Falcone says nitric acid can be used to melt away insulation from wire.
The fire department spent most of the day dealing with the substance and some windows on the home were boarded up.