Transcript for Someone called for help approximately 12 hours after fraternity pledge became unconscious

We turn next to new developments in the death of a student at Penn state falling down the stairs during a fraternity party. Several frat members accused of waiting at least 12 hours to call for help. Prosecutors saying the one student who spoke out to ABC news has become a target himself. And there's word tonight about cameras inside that frat house. Here's ABC's gio Benitez. Reporter: Today as more Penn state fraternity brothers in the death of Tim piazza. Reporter: Prosecutors in court today now accusing of one of brothers in intimidation. Is taking aim at kordel Davis after he told our robin Roberts that he begged in his fellow Reporter: But after his interview the prosecutor said it texted a message that nobody likes you anyway. 18 members of beta theta pi now facing charges, 8 facing charges of involuntary manslaughter and assault. And for the first time we hear that futile call for help. We have a friend who's unconscious, he's hasn't moved, probably going to need an ambulance. Reporter: One member calling 911 nearly 12 hours after piazza intoxicated following heavy drinking in an alleged hazing ritual, fell headfirst down a staircase. Okay, how old is he? He is 19? 19 years old. And was he breathing? He is breathing. Was there any alcohol or anything involved, do you know? Yes there is. Reporter: The D.A. Telling us high-def cameras in nearly every room captured piazza's suffering in agonizing detail for hours. By morning, 40 minutes before the 911 call, his skin color turning gray, his body stiffening. David, the fraternity brothers

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