NEWARK — A Union Township man has been charged with child endangerment in the case of a Newark boy whose death police called "sudden and suspicious."

Mark Harper, 36, was arrested Monday evening. The child has been identified as Aydin Brown, a second-grade student at University Charter School in Newark.

Essex County Chief Assistant Prosecutor Thomas Fennelly said Harper is the boyfriend of Aydin’s mother.

Harper was not charged with killing the child, who died at a hospital on Monday morning after being found passed out at home. An autopsy is being done by the New Jersey Northern Regional Medical Examiner’s Office in Newark to determine what caused the death.

Relatives told reporters that Harper had taken off and that police had been searching for him in order to question him about the boy.

Harper is being held in Essex County Jail, pending a detention hearing in Superior Court in Newark.

The investigation is ongoing. Anyone with information is asked to call the Prosecutor's Tips Line at 877-847-7432.

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