Rex Heuermann's Next-Door Neighbor Recalls Suspected Serial Killer Digging in Backyard and Frequently Burning Trash

Long Island Serial Killer suspect Rex Heuermann's next-door neighbor claimed he heard him digging in his backyard at odd hours and smelled burning trash coming from the yard, RadarOnline.com has learned.

The neighbor's claims came as Suffolk County police descended on the unsuspecting Massapequa Park home, where officials believe at least one victim was killed.

Heuermann, a Manhattan-based architect, was arrested outside of his office building on July 13 after police said DNA and cell phone data connected him to four victims discovered on Gilgo Beach in 2010.

For the last 15 years, Dominick Cancellieri lived next door to the Heuermanns. As Cancellieri looked back on those years for any clues, he recalled an incident of Heuermann allegedly digging in his backyard at a peculiar hour.

"When I was around 18 or 19 years old I was watching TV in my basement," Cancellieri told NewsNation. "I went outside at about one or two in the morning and heard digging in the backyard next door."

Cancellieri said that, at the time, it piqued his curiosity — but when he went to spy on Heuermann, a gut instinct stopped him.

"Now I really wanted to go and check out what it was and look through the fence but something stopped me from doing it," the next-door neighbor continued. "I was nervous I wasn't too sure what I was doing at the time."

Cancellieri added that in retrospect and "with everything coming to fruition," he wasn't surprised by Heuermann's accusations "in the slightest bit."

"He would burn his garbage and I would smell it, and I would always wonder 'Why is this guy burning his garbage again,'" Cancellieri said. "It seemed to be once every few weeks I would smell garbage burning again at his house."

Cancellieri also scrutinized a tense exchange he once had with Heuermann over a parking space. The neighbor said Heuermann's truck was parked halfway over his driveway, and when he spoke to him about it, the towering man was allegedly aggressive.

"I went out of my car and told him he had to move his car," Cancellieri claimed. "He got a little loud, and I got a little loud back and he ended up moving his car."

Never miss a story — sign up for the RadarOnline.com newsletter to get your daily dose of dope. Daily. Breaking. Celebrity news. All free.

Cancellieri's claims of Heuermann's strange behavior came as forensic crews descended upon their quiet Long Island neighborhood.

On Thursday, police cruisers were positioned in front of the home in an attempt to block nosey onlookers. Blue tents were set up as officials combed through the property, removing items from the home.

Officials were also seen digging in the various areas of Heuermann's backyard.

"Every incident, even the way he looked, made me think this guy is a weirdo and with everything that's come up," the neighbor continued as he noted, "this all makes sense to me now."