(NewsNation) — An ID connected to someone from the quadruple homicide in Moscow, Idaho, was found during one the searches of Bryan Kohberger’s residences, NewsNation has exclusively learned.

Police also believe they have evidence connecting Kohberger to alleged cyberstalking of someone from the Moscow residence where four University of Idaho students were killed in November.

Police arrested Kohberger in Pennsylvania at his parents’ home roughly six weeks after the fatal stabbings. Court documents have revealed police used DNA evidence left on a knife sheath at the scene to link him to the crime.

A search warrant unsealed earlier this year revealed police seized IDs from Kohberger’s car, but it did not specify to whom they belonged.

“It’s a big deal. That is a smoking license,” retired FBI agent Jennifer Coffindaffer said Thursday on “CUOMO.” “Just like the sheath was a smoking sheath found next to Maddie with his DNA on that clasp, it’s the same thing in this situation. Why would he have an ID related to one of those people from that house?”

The bodies of Xana Kernodle, Ethan Chapin, Madison Mogen and Kaylee Goncalves were found Nov. 13 inside the off-campus rental house they lived in. All were stabbed to death.

In addition to the DNA found on the knife sheath, police say cellphone tower data puts Kohberger near the scene of the crime immediately after the killings. Police have not recovered the murder weapon.

Police would not officially confirm the details of the license due to a gag order in the case, but high-profile trial attorney Mark Geragos said it would be a “hurdle” for the defense if presented in court.

NewsNation also learned exclusively Wednesday that authorities in Pennsylvania are investigating Kohberger for his potential involvement in other outstanding homicides.