CONWAY, SC (WBTW)-  A letter containing cocaine caused an evacuation at the Horry County Government and Justice Center on Friday.

“Components of the white powder substance resulted in a positive test consistent with cocaine,” said Brooke Holden, with Horry County Government. “The remaining components of the substance are currently being tested.”

On Friday, the center was evacuated after staff of the Horry County Solicitor’s Office received a letter through the U.S. Post Office that contained “a white powder,” according to a report from Horry County. The powder was reportedly examined and “determined not to be threat to public health.”

The center was later declared safe and employees and staff were allowed to return.

Holden previously told News13 that the solicitor’s office received an envelope on Friday containing a suspicious substance that was opened by an employee.

“The building was evacuated shortly after 1 p.m. as standard protocol,” said Holden.

People were evacuated from the building for nearly four hours. During that time, those who came in contact with the substance were quarantined. No one was injured.

The USPS is assisting the Horry County Sheriff’s Office with an ongoing investigation.

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