Jonathan Mejia, 24, was brought from the Bergen County Jail to Bronx Criminal Court, where he was formally charged Wednesday with murder, manslaughter and weapons possession.
Prosecutors said Mejia shot Daniel Valdez, 43, in victim's home near West 234th Street in the borough's Kingsbridge section after an argument got physical on May 2.
Valdez had let Mejia in, then was shot in the torso during the fight as family members sat in a nearby room, they said.
The father of two was later pronounced dead at NYC Health and Hospitals/Harlem (otherwise known as Harlem Hospital).
Daily Voice broke the news of Mejia’s arrest after he showed up with his mother in the emergency room at Hackensack University Medical Center the next day.
SEE: Fair Lawn Man, 24, Held In Uncle's Bronx Slaying After Going To HUMC Emergency Room
His mother "reported that Mejia may have shot and killed his uncle in the Bronx" the night before -- in what's formally known as avunculicide -- and had become suicidal, a ranking law enforcement official with knowledge of the circumstances told Daily Voice.
"She reported he did have a gun [on Monday]," the source added.
Mejia was charged locally with being a fugitive from justice and was taken, in custody, to Bergen New Bridge Medical Center in Paramus (because of his mental state) to await the outcome of extradition proceedings.
NYPD detectives came to New Jersey and were accompanied by Bergen County prosecutor's detectives and Fair Lawn police when they went to Mejia's mother's Madelyne Place home, among other locations.
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