This just in from a campus source:
Dear CSU Community:
At approximately 8:30 a.m., the CSU Police Department received a call of a male carrying a large rifle on the west side of the Clark Building. The CSUPD responded in less than one minute and did a cursory search of the building for the male subject. After a thorough search of the building, it was determined that the male subject was a History professor that brought the rifle for demonstration purposes for a civil war class.
As you can imagine, due to the seriousness of the call, CSUPD officers responded with shotguns and several were wearing plain clothes.
Again, the situation has been resolved and instructions on how to bring a rifle for demonstration purposes were given to the subject.
At no time was the Clark Building evacuated. Furthermore, students, faculty and staff were not in any danger. The building proctor of the Clark Building will send a notification to building offices to explain that everything is under control.
Thank you to all of those who called to notify the CSUPD of the situation. Your alertness, observation and accurate description of the subject are much appreciated.
Chief D. Yarbrough
CSU Police Department