Mr Johnston's body was discovered in the Maghera area on Wednesday night.
Following the discovery of a body in Maghera by police searching for high risk missing person Lee Johnston, a post mortem examination has concluded.
Superintendent Michael O’Loan, District Commander for Mid Ulster, said: “Police can confirm that this is the body of the high risk missing person Lee Johnston. His death is not being treated as suspicious at this time.
“Our thoughts today are very much with Lee’s family and friends as they mourn his loss.”
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