Artpark was temporarily evacuated last night after two bomb sniffing K9's detected a possible dangerous material near a speaker.
Randy Bachman and 54-40 were set to perform for this week's "Tuesday's in the Park" performance.
Long lines were scene waiting outside the park while police checked the scene.
As a precaution, State Park Police, the Erie County Bomb Squad, and the Federal Bureau of Alcohol, Tobacco, Firearms and Explosives responded to the Lewiston facility.
The scene was determined to be safe and the concert was allowed to go ahead.
It's unclear what may have caused the bomb-sniffing K-9s to react, and the situation is still under investigation.