Lake County police closed the County Government Center on Friday morning as part of an investigation of a possible biological agent in the complex's mailroom.

Sheriff's police Spokesman Michael Higgins said Building A was locked down and hundreds of county employees were asked to remain in their offices while a hazardous material team prepared to remove what was described as a suspicious substance for analysis. Everyone in both buildings A and B then was asked to leave the building until called back inside about 30 minutes later.

Hazmat investigators later determined the substance, in an envelope that had been sent to Judge Julie Cantrell, was not dangerous.

Lake County Commissioner Gerry Schueb authorized the shut-down mailroom to remain closed until it could be cleaned according to emergency management protocol.