BRYAN COUNTY, OK -- Just after Noon, a package was delivered to the Bryan County Court Clerk's office containing an unidentified white powder.
Everyone inside the building was evacuated and detained until military Hazmat crews found the white substance was not hazardous.
After nearly eight hours on lock down, law enforcement and military officials opened up the perimeter around the Bryan County Courthouse.
The area was on lock down after an unidentified white powder was discovered in one of the packages delivered to the court clerk's office
"We cleared most of the personnel out of the court house except those that were in the area at that time, then we just started staging people here at the courthouse and quarantined the area and isolated certain individuals that had actually come in physical contact with it," said Bryan County Sheriff Ken Golden.
Later Monday afternoon, Ardmore Hazmat crews, then a military haz mat crew from Norman went into the courthouse to investigate the white substance.
Lieutenant Colonel Scott Houck, says after sampling the powder they found it to be a benign substance.
"We're still in the process of sampling it right now, but based upon the systems and everything we've ran everything looks benign and so based upon that we were able to let some people go home for the night," Houck said.
Golden says the package had originally been delivered to the annex a couple days ago, but wasn't opened until Monday afternoon.
The few dozen people who were detained say officials made sure that everyone in the court house was evacuated calmly and safely.
"Everyone has been very orderly, very good humored but you know our law enforcement our fire department, our emergency managers everyone has done a great job of taking care of everyone here," said Investigator, David Cathey.
The courthouse will resume normal operations Tuesday.
Meanwhile, The Bryan County Sheriff's Office, along with the FBI, are investigating who may have sent the package.
Houck says crews are still trying to identify the white substance.
A sample has also been sent to the State Health Department to be identified.