Nile Diakos, 35, was recorded on phone calls and in texts admitting that he killed Alicia Arnone by stabbing her in the neck and chest last Saturday, March 26, according to court papers.
Authorities originally charged her former live-in boyfriend, Andrae Daniels of Lodi, with killing Arnone, 35.
But new information emerged that led them to drop murder charges against him and arrest Diakos, Bergen County Prosecutor Mark Musella said Thursday, March 31.
Responding to a 9:59 a.m. emergency call of a stabbing, Leonia police were met at the Grand Avenue apartment by Diakos and Arnone's 13-year-old daughter, a complaint on file in Superior Court in Hackensack says.
Diakos told them that his girlfriend was dead inside the unit.
They found her "lying face down in a pool of blood at the top of the stairs," with a knife near her head.
Arnone, who'd attended Palisades Park Junior-Senior High School decades ago, was pronounced dead at the scene by paramedics at 10:23 a.m.
Daniels was arrested after detectives interviewed Diakos and the young girl.
During the investigation that followed, Diakos spoke with an unidentified confidante who recorded their conversations, authorities said.
In those calls, they said, he confessed to stabbing Arnone multiple times.
Diakos also "admitted to leaving the residence because he heard the juvenile female coming from the bedroom," the complaint says.
He immediately circled back to the front of the home "as if he was just arriving on scene" in order to appear as if he "was just arriving at the residence as the juvenile female came running outside."
Investigators said they also have text messages in which he "implicated himself in the murder of Arnone, specifically stating he would turn himself in on multiple charges, including any murder charges brought on him as a result of this incident.
"Interviews were conducted on the recipient of said text messages, as well as the parties involved in recording his confession, in which law enforcement was able to corroborate the validity of the aforementioned statements," the complaint says.
"Based on the information obtained thus far in this investigation, coupled with eyewitness statements, it is evident that Nile Diakos is responsible for the death of Alicia Arnone," it says.
Authorities, family members and friends originally believed that the killer was Daniels after learning that he’d ignored a final restraining order she'd obtained after "multiple" incidents of domestic violence.
Arnone had her daughter with the violent career criminal, who has a 20-year criminal history mostly involving assaults, threats, harassment and violating restraining orders, records show.
Originally from Englewood, Daniels -- also known as "Andre" or "Dre" -- most recently had been arrested for violating a restraining order and harassment on Jan. 5 of this year. A judge in Hackensack released him on Jan. 14 with conditions that investigators said he didn't follow.
Daniels was released from the Bergen County Jail on Wednesday, March 30, Musella said.
Diakos, meanwhile, was seized and charged with first-degree murder, hindering and weapons offenses, the prosecutor said. He remains in the county lockup pending a first appearance in Central Judicial Processing Court in Hackensack.
The announcement was made on Thursday, March 31, the day of Arnone's wake.
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