There were bullet holes — in the door, and the wall, and even in the tile floor at the foot of the stairs — and scattered around the floor were dozens of brass cartridge casings. Someone with a cache of ammunition had made a stand in this apartment building, sometime after the day. Soon after, maybe even on, judging by the complete lack of fortification that had been done.
Zombies eat people. They don’t eat guns or ammunition, and they don’t police either up when they finally depart, hungry again, chasing some appetizing aroma on the wind. Riley started up the stairs.