Neighbor says he confronted suspected Gilgo Beach killer for leering over fence at his wife as she sunbathed

A longtime neighbor of the suspected Long Island serial killer revealed Tuesday several chilling encounters with Rex Heuermann, including behavior that left his wife "creeped out."

Etienne Devilliers, who has lived next door for nearly three decades, said he once confronted Heuermann for leering over the fence at his wife as she laid out in the sun.

"My wife would sunbathe in the backyard occasionally ... but he would stand over the fence because he was a tall guy. … He would constantly say he was 6'4'', 250 pounds, and he would try to start conversations with her," Devilliers said on "Fox & Friends."

Devilliers said he worked at the time as a New York City firefighter and that Heuermann's behavior mostly occurred while he was not at his suburban Massapequa Park home.

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"My wife finally told me a few times that she was getting creeped out a bit by him. I had a conversation with him. It wasn't pleasant. It wasn't a pleasant conversation. We spoke pretty harshly, but he didn't get aggressive or anything. After that, he never did it again," he recalled.

The initial incident occurred shortly after Devilliers and his wife moved to the neighborhood, but Heuermann still made an impression with his "odd" behavior.

"He was strange and odd," Devilliers said. "People would stay away from his house. I mean, they would literally cross the street because the house was such a mess."

Devilliers added that Heuermann tried to "buddy up" with other neighbors, but he tried to steer clear of the now-suspected killer.

"He tried to buddy up because he wanted some friends. Nobody in the neighborhood ever talked to the guy. The house was a mess, but he stayed to himself, pretty much. So, he asked me to play cards and tried to buddy up a couple of times, but I kind of stayed away from him."

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The 59-year-old Manhattan architect was arrested Thursday for the murders of sex workers Melissa Barthelemy, Megan Waterman and Amber Costello, whose bodies turned up on Gilgo Beach in 2010.

The father of two is also the prime suspect in the slaying of a fourth victim, Maureen Brainard-Barnes, according to prosecutors.

Devilliers said he was "really surprised" to find out Heuermann was charged with such violent acts, noting that while he was "strange," he did not come off as particularly aggressive.

"When I had that altercation with him, I basically threatened him to stop leering at my wife. He backed off. The violence thing I didn't see coming because he didn't come off violent. I mean, he was strange to look at, enormous. But he never became more violent to me or to anybody that I could tell," he added.

Suffolk County Police, however, told Fox News on Monday that Heuermann had an arsenal of weapons in his suburban Long Island home with more than 200 guns.

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Devilliers said that years ago, around the time of the killings, he noticed a large box being carried into Heuermann's home. He said he knew Heuermann was a "gun fanatic" but the size of the reported arsenal came as a shock to him.

"I saw a group of people carrying in a box that must have weighed a ton. And he told me it was a metal door for the basement. … But apparently now the detective that came to my house ... he said that it was a safe, into the wall of the basement. So, he told me the door was to lock up his guns, but I had no idea."

Devilliers said he "never saw" Heuermann's first wife but was familiar with the second wife and their two children.

"The wife was a bit on the odd side, too. She kept to herself most of the time, and whenever I spoke to her, it was just two or three-word things. With Rex, on the other hand, I had conversations with him regularly," he said.

"The kids, I really always felt sorry for the kids. The son is a special needs kid who just got his first dog a couple of weeks ago. It just brightened him up. He's a sweet kid. And they always used him to do the garden work and plow the snow. And they kept the kid busy doing the manual labor around the house," Devilliers continued.

"The daughter is also a nice young girl that kept to herself. Very quiet, very shy, and rarely I spoke to her – just hello and goodbye. The son I did have conversations with. He was a nice kid. I feel terrible for them."

Since Heuermann's arrest last week, Devilliers said the neighborhood has become a "madhouse" full of reporters and others interested in the case. He said the usually quiet neighborhood is in shock over the news that an suspected mass murderer was in their midst for years. 

"We're in shock. We really are," he told host Brian Kilmeade. "This is a wonderful neighborhood. The people around us are terrific. Everybody's really a nice person. We all get along. There's a lot of cops. I'm a retired city fireman, and there's a lot of cops and firemen in the neighborhood. So, we feel very, very safe. The kids run around, biking around. Everybody's happy here. So, this is a shock to all of us."

Fox News' Rebecca Rosenberg contributed to this report.

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