The Dona Ana County Sheriff's Department is investigating an assault involving three detainees in the juvenile section of the county Detention Center.
They say three of the juveniles involved could face felony charges.
Authorities say a 16-year-old detainee allegedly rushed a door-control panel around 11 a.m. Wednesday and opened three separate cell doors.
That allowed two other teenage detainees to enter the cell of a 14-year-old detainee.
They allegedly attacked him before being subdued with pepper spray.
The 14-year-old boy has been taken to a hospital for treatment of a fractured jaw.
Sheriff's detectives are interviewing staff and detainees about the attack, which appears to have been carefully planned.
They say a concurrent internal investigation has begun into how the incident occurred and whether any staff safety protocols were violated.
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