FREEHOLD, N.J. (CBSNewYork) — An 18-year-old man charged in the killing of an 11-year-old girl in Keansburg, New Jersey was told he would remain in jail until his trial.

Andreas Erazo faces first-degree murder and weapons charges in the death of Abbiegail Smith.

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The fifth grader’s body was found on July 13 behind the Hancock Arms apartments, a day after her mother reported her missing. Monmouth County prosecutors say Erazo, her upstairs neighbor, stabbed Abbiegail in the neck with a knife, killing her.

“This is one of the worst crimes I’ve seen, as alleged. Anytime there’s a child victim involved — and we’ve seen cases like this before at the prosecutor’s office — it’s truly heinous,” Monmouth County Prosecutor Christopher Gramiccioni said last week.

Police say Erazo lived in the apartment above the Smith family with his mother and another relative and say the murder took place in or near Erazo’s apartment.

As CBS2’s Meg Baker reported, a judge ruled that Erazo must remain in jail until his trial due to the severity of the crime, and the weight of the evidence.

Abbiegail’s family heard the gruesome details for the first time while sitting in court two weeks ago.

On Wednesday, they wore white t-shirts with the 5th grader’s picture on it, crying as they learned the gruesome details of her murder.

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“She was bound with cord from the computer, and most of the clothing removed, evidence of traumatic injury to both sides of the neck,” Prosecutor Diane Aifer said.

The defense argued that Erazo should be released as he awaits trial.

“The charges at this juncture are just that charges, allegations brought forth by the state,” defense attorney Courtney Schneider said.

Erazo allegedly confessed during a 9 hour interrogation.

“Erazo was scared, confused, vulnerable, and did not have an attorney present,” Aifer said.

Another factor in the judge’s decision to detain Erazo is a juvenile charge for unlawful possession of a weapon.

Prosecutors are calling the killing an isolated crime.

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The little girl was laid to rest this week.