Butler city police Tuesday afternoon were investigating a possible methamphetamine lab in a house on the 300 block of West Cunningham Street.

City officers were assisted at the scene by officers with the state police's Clandestine Lab Response Team. Officers, wearing gas masks or surgical masks, spent more than an hour bagging and processing evidence on the front lawn of the house.

City police declined to comment on the bust Tuesday night, saying it was an ongoing investigation.