As we sat inside a student’s tiny dorm room on the UMass campus in Amherst, he pulled out a large suitcase, zipped it open and proudly revealed an arsenal of guns and ammunition.

My producer Meredith and I couldn’t believe it!

Why in the world would he and his roommate waste so much valuable space with a bunch of plastic Nerf guns?

It’s all in the name of a game called Humans Versus Zombies, or HvZ for the cool people.

It’s apparently an addictive form of adult tag.

We heard stories of students wearing camouflage and hiding in the trees to avoid being “tagged” … a Zombie who hid under a pile of leaves in freezing weather at 2:30 in the morning just to nab a Human and even a story of a student jumping out of a second story window to “tag” another student. Some students have been known to hide out in their dorms and never leave until the game is over.

HvZ has been played at college campuses long before the Virginia Tech massacre and variations even before that.

But recently the game has come under scrutiny because of those brightly colored plastic Nerf guns.

Alfred University in western New York was placed under lockdown a few weeks ago after someone called police about a man on campus with a gun.

You guessed it … he was playing Humans vs Zombies, but he made the mistake of concealing his weapon so that only his hand on the pistol grip was visible.

The gun is a bright yellow with orange, black and silver accents. Fully revealed you wouldn’t mistake it for a real gun, but with only the grip showing… it’s apparently possible.

The student didn’t mean to cause any panic, but the administration has now put the game on hold and will likely ban the guns.

Back on the UMass Amherst campus, players still have their guns and so far the administration hasn’t felt the need to restrict them.

The UMass students we spoke to said they don’t want to give them up, but will if it means keeping the game alive.

After all, the humans would still have their balled up socks and marshmallows to ward off the Zombies.