Police blame a modern game of tag called "Humans Versus Zombies" for wasting public safety resources this week after two reports of gun calls tied to the competition.
The game pits a zombie team against a human team, which tries to "stun" the zombies with Nerf guns to avoid getting tagged.
About 230 people are participating on the University of Wisconsin-Madison campus this week, part of a competition played on campuses across the country.
A passerby reported an automatic weapon on campus Thursday morning, and UW Police responded, only to find out the gun was a toy used in the game. It was the second such call in as many days.
"It is an absolute waste of police resources," said Marc Lovicott, a UW Police spokesman. "Most of our officers went out there because it is a serious incident."
Lovicott said the game's organizers are good about telling police when the game will be played every semester.
But with heightened suspicions after the Boston bombings, poison sent to the White House, and a concerning powder found at a Beloit health clinic, police will consider whether to allow "Humans Versus Zombies" to continue in the future, Lovicott said.
On campus, about a dozen students wearing orange bandannas played outside Sterling Hall on Thursday afternoon.
"I wouldn't think that any of the Nerf blasters would confuse anyone for a real weapon, because most of the new ones are bright yellow or blue," said Steven Brandt, a UW freshman on the zombie team.
"Most school shootings happen from people who are isolated and on their own," he said. "With 'Humans Versus Zombies,' I've made a whole bunch of friends -- it brings people together."