LAWRENCE, Kan. -- University of Kansas officials say there have been no shots fired or injuries amid a report of a possible armed person at a residence hall.

Police began a room-to-room search of 10-story McCollum Hall around 2 p.m. Friday, as the university used its campus-wide alert system to warn students to stay away from the building.

The university was not under lockdown, but students in McCollum were told to stay in their rooms. It's the largest residence hall on campus, housing about 900 students.

The search was still under way around 4 p.m.

University spokeswoman Jill Jess says the search began when a resident reported hearing an argument in an adjacent room and a man saying, "Where's my gun?" That student reported the remark to the front desk, which called campus security.