Police say 55-year-old Brian Gooney's body was discovered along the Rahway River.
He last seen leaving his apartment in Rahway at around 9 p.m. on March 9.
Gooney was a paraprofessional at Soehl Middle School in Linden.
School staff and students had been hoping for his safe return.
Flyers were distributed throughout the county in hopes of finding Gooney.
Linden Public Schools staff also held a "Bring Brian Home" gathering, to raise awareness about his disappearance.
An autopsy will try to determine the cause of his death.
The incident is under investigation, and police ask that anyone with information please contact Detective Tilton at 732-827-2146, or the Rahway Police Department TIPS Line at 732-388-1553.
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