In this sneak peek of the episode, we see Hanna (Ashley Benson) sobbing as a body is put onto an ambulance. Meanwhile, a policeman questions Emily (Shay Mitchell), asking "the deceased was a friend of yours?" and "I'm trying to understand what happened. Did you know the victim?" It looks like there are two bodies, so it might be that one person is alive and injured, and one is dead.
Emily says she DID know the victim, though she doesn't answer the friend question. Who do you think it is?