FORT COLLINS, Colo. (KDVR) — A suspect was arrested after two Colorado State University students were reportedly harassed on campus and had a knife pulled on them.

The incident was reported at 9:55 a.m. Wednesday near the recreation center on the main campus, according to the CSU Police Department. The suspect, identified only as a male, was not a university student or employee.

“While this situation is not the norm on our campuses and was very unusual, the quick thinking of bystanders and the de-escalation skills used by our officers made a significant difference in the outcome of this incident,” CSU Police Chief Jay Callaghan said in a statement.

Police gave this account of the incident:

The male visitor asked a female student who was walking near the Rec Center for directions to another campus location, and then began yelling at her. The male suspect then approached the female student and grabbed her by the arm while continuing to yell at her. A bystander student intervened on her behalf. The suspect threatened the two students with a knife and walked away. The students were not injured.

Colorado State University Police Department

Police were on the scene within minutes of the emergency call, and witnesses helped them identify the suspect.

The suspect was arrested on counts of felony menacing, harassment and false imprisonment and was booked into the Larimer County jail.

The incident happened while other police officers and the Larimer County SWAT team were on campus for an annual walkthrough of Canvas Stadium before fall sports season. CSU said their presentence was unrelated to the incident.