Police have referred themselves to the watchdog after a body thought to be that of a missing teenager was found.
Ronnie Benjamin, 18, who also had links to Romford, was reported missing on Thursday at Brentwood in Essex.
Essex Police said the search for Ronnie had been called off after the body was found in Brentwood on Sunday.
They added that although formal identification was yet to be confirmed, the teenager's family had been told and were being supported by officers.
A spokesman said: "Our thoughts continue to be with Ronnie’s family and loved ones at this very difficult time."
Essex Police said the force had referred itself to the Independent Office of Police Conduct because the case met the criteria for investigation.
The watchdog will examine if any earlier opportunities to find Ronnie had been missed.
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