Transcript for Pa. Doctor Killing: Person of Interest in Custody
pediatrician murder mystery and the breaking developments overnight. Police raid the home of a nearby exterminator. He's in custody now. And alex marquardt is o the scene with the latest. Good morning, alex. Reporter: Good morning, george. While sources tell abc news, the police do believe they have the man in custody who killed the beloved doctor, what remains baffling this morning is whether the man had any connection with the woman he allegedly killed. Overnight, police raided this philadelphia home. Investigators could be seen bringing bags of evidence to police vehicles outside the home. Sources tell abc news that the man being questioned this morning is a 37-year-old exterminator who lives with his girlfriend and a child. Someone with a steady job and a home still decorated for christmas. He's outside, always playing with his children. He doesn't seem like that kind of guy. Reporter: But police sources say surveillance video from multiple cameras shows the same man may be a killer. It shows him following melissa into her home. Sources say this silver ford pickup truck being towed from outside of his house, was seen on camera in the popular doctor's neighborhood on the day of the killing. And sources tell wpvi it contains evidence. They have something that connects the bad guy to the victim. Whether it be videotape, and/or forensic evidence from the crime scene. Reporter: Investigators have been working around the clock since finding her body on fire in the basement of her row house on monday. She had been bound and strangled. There were no signs of a struggle or a break-in. The police have found no connection between the man and the doctor. But they add that an arrest could come as early as this morning. Meanwhile, police have been questioning the man's girlfriend and mother. We're told they have been cooperating.
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