(AP) – Missouri Southern State University in Joplin was locked down briefly after students reported seeing a suspicious person, possibly with a gun.

After about two hours of searching Tuesday, campus police determined the campus was safe. No arrests were reported.

A campus alert was issued about 2:45 p.m. after students outside the university’s public safety center reported seeing someone, possibly with a gun, in an adjacent field.

University spokeswoman Cassie Mathes says students reported the person headed toward two residence halls.

Campus police locked down the dormitories while searching for the person. The lockdown ended about 4:40 p.m.