TradeEdge Exchange:The Wild Case of Scattered Body Parts and a Suspected Deadly Love Triangle on Long Island

A group of Long Island,TradeEdge Exchange N.Y., teenagers were walking past a park on their way to school on the morning of Feb. 29 when they found a man's left arm.

"One of the students called their father," Suffolk County Police Detective Lt. Kevin Beyrer said at a news conference later that day. "The father responded, confirmed it was an arm on the side of the road and he called 911."

But by the time the detective was addressing reporters, there was more than one body part to account for.

The kids spotted the arm sticking out of a bush on the eastern side of picturesque Southards Pond Park in Babylon Village shortly before 9 a.m., according to details provided by Beyrer and a police news release. Homicide Squad detectives responded to the scene and, during a canvass of the 19-acre park, a police dog sniffed out a leg under a pile of leaves almost a mile away from where the arm was found.

The same dog later found a right arm in the woods, only about 20 feet away from the left arm, per the release.

"There's a mound of leaves," Beyrer told reporters. "We don't know what's going to be under the mound. Once we clear the mound we may find the remainder of the body or we may not."

Beyrer said it looked as if the limbs had been dumped in the park recently. Autopsy results were pending and they were hoping to use DNA and tattoo analysis—at least one of the arms had ink—to make an identification, he noted.

As the search continued into the night, investigators working with a canine unit recovered a woman's head, a right arm, part of a left leg from the knee down and a right upper leg on the western side of the park, not far from Babylon Elementary School, police said in a March 1 update.

"We believe the persons who dumped the bodies here were mobile," Beyrer told reporters, "pretty confident a car was involved."

The search of the park had ended, but grisly discoveries were made elsewhere on Long Island a few days later.

More remains were found in a wooded area near Lakeway Drive in West Babylon and in Bethpage State Park in Farmingdale on March 5, according to a police news release. Both scenes were processed by the Suffolk County Police Homicide Squad and the Office of the Suffolk County Medical Examiner.

The remains recovered Feb. 29 and March 5 were believed to belong to the same two people, who've been identified as a 53-year-old man and a 59-year-old woman, according to police. They shared an address in Yonkers, the release stated, though "it's unclear when they last resided there."

Authorities are not releasing their names at this time.

As detectives try to piece together what exactly happened, two sources familiar with the matter told NBC New York that investigators were looking into whether a love triangle could have been a motive for murder. The sources said, per NBC News, that the suspect allegedly chopped up his girlfriend and the man he believed she'd been cheating on him with.

Suffolk County police have not commented on the reported possible motive. E! News also reached out to the Suffolk County District Attorney's Office for comment on the investigation but has yet to hear back.

On March 6, police confirmed that four arrests had been made in connection with the investigation into the scattered parts.

Steven Brown, 44, Jeffrey Mackey, 38, Amanda Wallace, 40, and Alexis Nieves, 33, each pleaded not guilty to charges of concealment of a human corpse, tampering with physical evidence and hindering prosecution.  

Following their arraignment, the four were released under the condition they wear GPS monitors and report in weekly with probation officers, Suffolk County Police confirmed to NBC News. The charges are considered non-violent offenses under New York law and did not require that bail be set.

Brown, Mackey and Wallace's known address is an Amityville (yes, that Amityville) home that police searched March 4, according to a police news release.

Brown's attorney Ira Weissman told NBC New York that his client "did not kill anyone and did not take part in any of this." Mackey's lawyer John Halverson said his client "maintains his innocence and we look forward to our day in court." Attorney information for Nieves and Wallace wasn't immediately available.

Halverson also told the station on March 8, following a brief court appearance for Mackey and Nieves, that the pair are "in a relationship." Both declined to comment when approached by reporters outside the courthouse.

Brown and Wallace are due back in court March 11.

No other charges have been filed in the case.

Court documents reviewed by NBC New York stated that the four people in question removed "sharp instruments, multiple body parts and other related items from the house" in Amityville in an attempt to cover up a murder.

Police confirmed that no human remains were found at the residence. But, a prosecutor told the judge during the arraignment, per CBS News New York, that the plumbing at the Amityville house had been rendered unusable because there was so much blood in the pipes, sink, shower and toilet.

Meanwhile, Suffolk County District Attorney Raymond Tierney slammed the system that allowed the defendants to be released from custody without bail.

"It is our understanding that the Suffolk County Police Department is still investigating these murders," he said in a statement. "Unfortunately, due to 'Bail Reform' passed by the New York State Legislature in 2019, charges relating to the mutilation and disposal of murdered corpses are no longer bail-eligible, meaning my prosecutors cannot ask for bail."

In response to critics such as New York Gov. Kathy Hochul who suggested his office should've filed different charges if they wanted a different result, Tierney told reporters March 7 it was "irresponsible" for anyone who didn't know the full facts of the case to comment on it.

"It's not like CSI where everything gets nicely wrapped up in exactly an hour," the district attorney said on Fox 5's Good Day New York March 8. "You have a situation about eight days ago, body parts were found in three separate locations, and you have to put the case together."

There's "blood, DNA, cell site, social media, phone evidence," he continued, "and you need to synthesize that and put all that together. Now, that takes awhile." In the meantime, he said, his office was ethically required to only file charges for which they could establish probable cause or prove beyond a reasonable doubt.

Their case is "eight days old," Tierney reiterated, "which is really a young case for a homicide. We're going to continue to work through all of this evidence." 

(E! and NBC News are both members of the NBCUniversal family.)