Students at the University of Colorado are being told by campus police that their planned game of "Humans vs. Zombies" must be canceled because of a campus ban on toys that look like guns.

The planned game would divide participants into "humans" and "zombies" with the human team defending themselves with NERF guns. Campus police "[fear] they could be painted to look like a real weapon and someone could become alarmed and notify authorities, who would have to respond."

"If we have people playing a game and someone happens to be walking and sees someone crouched down with something that looks like a weapon, then they call us, we're going to respond," said campus police spokesman Mollie Bosley.