The search of accused Gilgo Beach serial killer Rex Heuermann's home shows no signs of slowing down, but experts are offering a hint as to what police could be looking for.

Hofstra University Law professor Fred Klein says Heuermann's arrest in connection to the deaths of Megan Waterman, Amber Costello and Melissa Barthelemy means Suffolk County police are certain they have the right suspect, even if they had to move in on him earlier than planned.

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"The DA has kind of hunted at this - that they weren't ready to arrest him right when they did, but something happened that either spooked him or they felt he was likely to commit another crime," Klein says.

Klein says police could be looking for evidence that Heuermann could have kept as "souvenirs" from his murder victims. He says jewelry, clothing or any personal belongings could be a "game changer" if and when the case goes to trial.

"If they could find something like that in his car, home or place of business or maybe some other forensic evidence that might link that location to the crime scene, that would really be strong evidence," Klein says.

The Long Island college professor says he thought it was surprising that Heuermann allegedly left his victims' bodies in the same location. He says some serial killers place bodies in random locations to throw off authorities and make things look random.

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Klein also said that it's unlikely that the trial would move from Suffolk County, despite it being a high-profile case.