(BLACKFOOT) – A suspicious envelope containing a white powdered substance was found at the Bingham County Courthouse Friday. County commissioners say the envelope was found at about 10:30 a.m., which prompted a lockdown of the entire facility at around noon. About 300 people were kept inside the building until 4:30 p.m., when HAZMAT crews determined the powder posed no immediate threat. Officials say the substance will be sent to Boise for further testing. The envelope had a return address, but investigators don’t believe the sender had any criminal intent.