A woman’s body has been found in bushland in Sydney’s southwest.

Police were called to a reserve off Irwin Street, at Werrington, about 1.15pm on Sunday.

A crime scene has been set up and homicide detectives have been called to the scene.

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Officers are currently canvassing the area with the assistance of PolAir.

The area where she was found was a remote part of the reserve, which backs onto sporting fields and a residential area.

A passerby stumbled across the woman and contacted police.

Detective Superintendent Trent King said the reserve is “quite isolated” and it appears the woman had been there for “a period of time”.

He said there were items located around her body, including clothes and rubbish, but she was not wrapped in any material.

King said the woman appeared to be middle-aged, but investigations are still underway to determine her identity and age.

“We are in the infancy in this investigation, the scene is currently being examined by specialist police,” King told reporters on Sunday.

“I don’t have any information on injuries at this stage.”

King said the missing persons unit is assisting with the investigation as detectives work to ascertain the woman’s identity.

NSW Police have launched Strike Force Dowerin to investigate the incident.

King said homicide detectives are helping to assist with the case as police work to determine whether the death is suspicious.

“Until we identify the cause of death, a death is unexplained,” King said.

“And certainly, in this circumstance, we feel it necessary to take it to the highest level until we can disprove that situation.”

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