'He would give you the world': Father, 39, identified as body found at Sydney paddock

John Birch, 39, has been identified as the body found at a paddock in Sydney's north-west as police work on a new theory surrounding his death.

Officers were searching for a missing man when they found suspected human remains under a tarp near a home in Glenorie about 11am yesterday.

Tonight, the father and friend is being remembered as a big character with an even bigger heart.

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"It's sad for anybody to have to end their life in such a tragic way," his friend Kerry Gillett told 9News.

"If he liked you, he would give you the world. If he could, if he had it, he shared it."

Police are investigating whether Birch had been run down by a ute on Gleness St about 6am yesterday.

Neighbours reported hearing a bang.

"Up on the corner of Cat Eye Ridge Road and Gleness, there was a bang early in the morning," Glenorie resident Bob said.

Birch did not live there but regularly frequented a house about 100 metres down the road.

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That house was crawling with detectives and forensics specialists who had spent the last 24 hours collecting evidence.

The occupants of the home, two men and a woman, were arrested yesterday and questioned overnight.

They have all since been released without charge.

While they were in custody, an unknown person tried to break into the home to search for drugs and cash.

Investigations remain ongoing as police await the results of a post-mortem examination.

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