Miss Haigh was reported missing on June 19, 2002 after she failed to return to her home at Kingsvale, where she and her six-month-old son had been living with a married couple.

Following extensive investigations, a man and woman, both aged 61, were arrested at a property at Harden about 7.30am on Wednesday.

The man and woman were both taken to Young Police Station and have since been charged with one count each of murder.

Additionally, the man has been charged with aggravated sexual assault - victim with serious intellectual disability.

They were refused bail to appear at Cowra Local Court on Thursday.

EARLIER: A man and woman have been arrested in the Riverina and are expected to be charged with murder in relation to the disappearance of Amber Haigh in 2002.

About 7.30am on Wednesday, detectives from the Homicide Squad arrested a man and woman, both aged 61, at a property in Harden.

The pair have been taken to Young Police Station, where it is expected they will be charged with murder.

Miss Haigh was reported missing in June 2002 after she failed to return to her home at Kingsvale, 135km north-east of Wagga.

Police were told Miss Haigh was dropped off at Campbelltown Train Station on June 5, 2002, where she intended to travel by train to Mt Druitt to visit her sick father in hospital.

About 8.45pm the same day, money was withdrawn from her bank account from an ATM in Campbelltown.

A 2011 coronial inquest found Miss Haigh to be deceased, having died as a result of homicide or other misadventure in June of 2002.

Deputy State Coroner Scott Mitchell found that she was most likely murdered and her body possibly disposed of down a disused mine shaft.

IN OTHER NEWS:

Despite extensive investigations by police over the almost 20-years since her disappearance - including numerous public appeals and a reward for information - Miss Haigh has not been located and the circumstances of her disappearance remain undetermined.

In 2020, a formal review of the case was conducted under the Homicide Squad's Unsolved Homicide framework and a re-investigation commenced by detectives attached to Strike Force Villamar II.

The Wednesday morning arrest follows extensive investigations, with the NSW Police Force and NSW Government last month increasing the reward for information relating to Miss Haigh's suspected murder to $1 million.

On April 28, strike force detectives had travelled to Thurgoona and seized a white Suzuki Sierra for further forensic examination.

Detective Superintendent Danny Doherty will today address the media in relation to this matter at the NSW Police Headquarters in Parramatta.

Miss Haigh was 160 centimetres tall, of thin build, with brown hair and green/hazel coloured eyes.

Anyone with information that may assist Strike Force Villamar II investigators is urged to contact Crime Stoppers on 1800 333 000 or https://nsw.crimestoppers.com.au.

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