The 28-year-old Washington State University criminology doctoral candidate was arrested in Mount Pocono on Friday, Dec. 30, and charged with quadruple murder in the stabbing deaths of four University of Idaho students on Nov. 13.
Kohberger remained in the Monroe County lockup until his hearing Tuesday.
During a press conference that followed, Pennsylvania State Police Maj. Christopher L. Paris said that, under Idaho law, none of the details in the probable cause affidavit against Kohberger can be revealed until he is officially charged and processed in that state.
It's still not clear when he's expected to arrive in Idaho.
Moscow Police Chief confirmed to Fox News on Saturday, Dec. 31 that investigators believe the grad student acted alone when he allegedly killed Madison Mogan, Kaylee Goncalves, Xana Kernodle, and Ethan Chapin.
During his stay at the Monroe County lockup, a fellow inmate has accused Kohberger of making violent threats to corrections staff and exposing himself to guards, as Daily Voice reported.
Police have not disclosed a possible motive for the killings or said Kohberger even personally knew his alleged victims, though he apparently followed at least two of them on Instagram.
Monroe County Chief Public Defender Jason LaBar, who is representing Kohberger in the extradition process in Pennsylvania, told The Today Show Tuesday his client waived the extradition to sooner clear his name.
"He said this is not him," LaBar told NBC. "He believes he's going to be exonerated. That's what he believes, those were his words."
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