NEWARK — An alleged North Jersey serial killer was nabbed by an online sting operation launched by the friends and family of his final victim, prosecutors said Wednesday at the opening of Khalil Wheeler-Weaver's triple murder trial.

Wheeler-Weaver made a "fatal mistake” in killing Sarah Butler, a 20-year-old college student from Montclair, Essex County Assistant Prosecutor Adam Wells told the jury. Butler's desperate parents, sister and a friend created a fake online profile that lured the man to a supposed assignation that turned out to be a meeting with police, he said.

"Sarah's friends and family are the heroes of this case," Wells said.

Wheeler-Weaver, of Orange, is charged with strangling and asphyxiating Butler and two other women in brutal murders in the fall of 2016. He’s also accused in the attempted murder of a fourth woman, who survived only after she awoke from a drug-induced sleep and escaped from Wheeler-Weaver, authorities say.

Public defender Deidre McMahon told the jury that Wheeler-Weaver did not deny being with the victims before they disappeared, but he had left them safe and then cooperated with "numerous" police departments as a person of interest after the women were reported missing.

"That is not the conduct of a guilty individual," McMahon said.

Except for Butler, all of Wheeler-Weaver's alleged victims were sex workers. His strategy was to select women who were vulnerable because they "wouldn't be missed," said Wells.

Robin West, 19, his first victim, had to be identified through dental records after her burned body was found on Sept. 1 in a vacant home in Orange that was set on fire, authorities said.

Location tracking on Wheeler-Weaver's phone put him at the address of the house just before the fire, and, after driving away via 280 West, he circled back to watch firefighters battle the blaze, the prosecutor said.

The remains of his second alleged victim, 33-year-old Joanne Browne, were found at a vacant home in Orange. She had been struggling with homelessness and mental illness, her mother testified.

The would-be fourth victim, "T.T.", will testify during the trial about her terrifying ordeal, waking up in the back seat of her car with duct tape on her face and getting "choked back to sleep," Wells said. Eventually she managed to loosen the tape by "screaming and crying" and convince Wheeler-Weaver to take her to the Ritz motel in Elizabeth, to retrieve some belongings.

Jurors watched the hotel's security camera footage showing how T.T. managed to escape her captor by slamming and locking the door while Wheeler-Weaver was waiting outside.

Butler, a Montclair High School graduate and student at New Jersey City University, was home from college for Thanksgiving break in 2016 when she disappeared. More than a week later, on Dec. 1, her body was found in the 400-acre Eagle Rock Reservation in West Orange. She was a longtime dancer with Premier Dance Theatre in Montclair and a lifeguard at the local YMCA.

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Wells described the alleged slayings in gruesome detail in his opening statement, explaining how Wheeler-Weaver allegedly wrapped his victims' heads in packing tape, covering their noses and mouths, and then strangled them with items of clothing.

Jurors were told that there was a lot of evidence to go through and that it would be a long trial.

Mobile-phone records will show Wheeler-Weaver used his phone "to ask about date rape drugs," said Wells. "He asked it how to make home-made poison. He asked it how to put someone to sleep."

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Butler's mother Lavern became emotional when the prosecutor showed her a picture of her daughter and asked her to identify the woman in the photo. "That's my baby," she said softly.

She testified that she picked up her daughter in Jersey City on Nov. 22, 2016 and brought her home to Montclair for Thanksgiving break about 8 p.m. Butler then asked her mother for the keys to the van so she could "see a friend" that evening, and her mother agreed. Her daughter said she'd be out just a couple of hours.

Her mother never saw her again.

When she hadn't returned by morning, and hadn't answered her phone, her family became alarmed. Lavern Butler said she began calling all her daughter's friends, the Montclair police and the hospital. No one had any answers.

Knowing Butler's passwords, her sister and a friend got into her computer and found the interactions between Wheeler-Weaver and Butler on a social media website called Tagged, Wells said. They created a fake profile to attract Wheeler-Weaver and, working with the Montclair Police, arranged the sting operation.

Though Tagged is often used to solicit sex for money, it was "not what Butler was about," Wells said. She had communicated with Wheeler-Weaver on the site in the past and backed out of an in-person meeting, according to the prosecutor.

"This time, she went," Wells said. "It was the last mistake she ever made."

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Julia Martin covers Montclair for NorthJersey.com. For unlimited access to the most important news from your local community, please subscribe or activate your digital account today.

Email: jmartin@gannettnj.com Twitter: @TheWriteJulia

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