Detective Lt. William Duran said police issued a delinquency complaint charging the girl with aggravated assault after determining the severity of the victim's injury, which her mother said required 25 stitches to close.
The girl also needed plastic surgery after being "viciously attacked" at school by her fellow sophomore on Nov. 19, the mom said.
"Her ear was ripped in half, and by the grace of God was able to be stitched back together," she said.
The investigation that produced the delinquency complaint included a review of video surveillance and witness accounts.
Such cases are heard behind closed doors in the Family Part of Superior Court in Hackensack because of the accused assailant's age.
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