During the Office Complex chapter, one two occasions (one accidental, one Induced) a zombie was chasing me, and then altered its course slightly to hit a prop in front of me. I Then moved the prop off to the side.
The zombie continued to follow the prop, until the zombie was positioned between me and the prop. It then used its normal item-throwing swing, except the prop instead seemed to be hit into the zombie, instantly gibbing itself.
tl;dr zombie follows prop away from player, hits prop, dies.