The body of man found partially buried at a property in Sydney’s northwest has been identified.

Johnny Birch, 40, was discovered by police in a shallow grave in a paddock on Geleness Place in Glenorie about 11.30am on Friday.

NSW Police said officers made the grisly find when they went to the home as part of inquiries into a missing man, who lives in the Nepean area.

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Mr Birch was reported missing by a family member at 9pm the night before.

“On arrival, officers located what is believed to be human remains,” police said in a statement, adding the “incident is being treated as suspicious”.

Hills Police Area Commander Detective Superintendent Naomi Moore told media on Friday the human remains were discovered in a paddock a few hundred metres from the house covered in items.

Det. Supt. Moore said three people — two men and a woman ranging in their 20s to 30s — were arrested nearby shortly after the discovery and are assisting police with inquiries.

“They all come from an address in that street that police believe have some connection to the missing person we were looking into,” she said.

Detectives are currently waiting for results from a post-mortem examination. No charges have been laid.

Strike Force Haldren has been established to investigate the circumstances surrounding Mr Birch’s death and crime scenes have been established at the house and the paddock.

Anyone with information is urged to come forward and contact Crime Stoppers on 1800 333 000.