UPDATE: 11.56am: Police have removed a body from a Housing NSW unit complex off Howarth Place, Mangerton, where remains were discovered just before midnight on Thursday.

Forensic police left the stand alone building, that has been the focus of the police investigation, with a number of evidence bags just after 11.30am. A police dog squad dog entered the crime scene around 10.45am.

Part of the police search has focussed on a steep overgrown enbankment within the grounds of the housing complex. Investigators have had to contend with consistent rain while undertaking the search.

UPDATE: 10.30am: Riot squad police and the dog squad are among dozens of police at the scene in Mangerton where human remains have been found.

Police have conducted a grid search across the lawns at the end of Howarth Place, a cul-de-sac, where the police operation is focussed.

Earlier police removed two surfboards from a small stand alone building near Howarth Place.

Residents say the building that is the centre of the police investigation is a well known drug haunt.

The activity has attracted the interest of residents in the Housing NSW complex, and residents who come and go from their homes are being questioned about their movements.

Much of the complex has been cordoned off with police tape.

UPDATE: 10.06am: Police will address the media at 1pm on Friday regarding the disovery of human remains in a unit block in Crana Place, Mangerton.

UPDATE: 9.43am: A nearby resident, said police activity was centred around a small stand alone building at the complex.

"I walk my dog past there every day and regularly you'll see junkies there shooting up," she said.

"If they've found a body it will be in the laundry."

The woman said the issues with drugs had escalated in recent years, despite regular complaints to Housing NSW.

"They should at least clean it up," she said.

UPDATE: 8.47am: A resident from a unit in the complex adjacent to Rowland Ave said the three rear aprtment blocks had been closed off by police.

UPDATE: 8.18am: Police are door knocking the Housing NSW complex where the remains were found.

There are four unit blocks in the complex.

BREAKING: Police have discovered what are believed to be human remains at a unit block in Mangerton.

Officers were called to the property on Crana Place in Mangerton just before midnight on Thursday.

They discovered the remains in an external building within the complex, police said.

A NSW Police spokeswoman said the remains would have to be examined to determine whether they were human, however initial investigations suggested they were.

She could not provide any further information about exactly where the remains were found, or what condition they were in.

Police have set up a crime scene on Crana Place, a short cul-de-sac surrounded by a number of large unit blocks.

"Police have advised there may be some disruption for nearby residents while specialist officers process the scene," police said in a statement.