A suspicious package raised concern at the Ames Post Office Tuesday. Jim Robinson of the Ames Police Department says the postal service received a small package that had a stain coming through the package and police, fire and HAZMAT officials were called in.

Robinson says they eventually determined that the substance in the package was not hazardous. Robinson says they’re trying to determine why the material was being sent through he mail.

Robinson says they don’t know who sent the package and are working with postal inspectors trying to determine its origin. Robinson says the post office’s back delivery area was closed, but business continued at the front windows as they tried to identify the substance in the package.