A police statement has revealed that "prison informant" Peter Foster claims accused murderer John Chardon told him he weighted down and disposed of Novy Chardon's body in the Gold Coast Seaway.

Mr Chardon is facing a committal hearing in the Brisbane Magistrates Court, charged with the alleged murder of his 34-year-old wife Novy.

The mother of two disappeared from her Upper Coomera home on Queensland's Gold Coast in 2013 and her remains have never been found.

During the hearing, Foster told the court Mr Chardon had told him he shot his wife using a handgun with a makeshift silencer. In Foster's police statement, he said Mr Chardon told him he then dumped the body in the seaway.

According to Foster's police statement:

"John told me that he put Novy in the seaway after 8:00pm when the tide was running out to sea until midnight. "John then said, 'I weighted her with moderate weights so she would go under'. "John then said … she would have shot out of the seaway like a torpedo."

The court had heard Foster, a convicted conman, shared a prison cell with Mr Chardon (who was in jail at the time for other matters) for six weeks in 2015.

Foster claimed he acted as a police informant to get a confession.

'Shot her in the back of the head'

Foster told the court Mr Chardon had a meltdown one night, began crying and confessed to killing his wife.

"He mentioned about a plastic one-litre soft drink bottle that he used to make a silencer," Foster told the hearing.

John Chardon was arrested in 2016 for his wife's alleged murder. ( ABC TV News )

"He used words to the effect of 'a silencer turns a bang into a pop'.

"He [Mr Chardon] told me he shot her [Novy] in the back of the head."

Foster told the court Mr Chardon told him that he had worn disposable overalls during the killing so there would be no forensic evidence.

"He said ammonia and water washes away DNA and forensic," Foster told the hearing.

The court heard listening devices were to be installed the day after the alleged confession, so it was not recorded.

"I took an accurate record of it the next morning in my book," Foster told the court.

Foster is currently being held in a New South Wales prison on unrelated charges. ( AAP: Dan Peled - file photo )

Alleged confession does not match Foster's prison notes

During cross-examination, Mr Chardon's defence barrister Tony Kimmins questioned Foster's statement to police about the alleged confession and said it had not matched his prison notes.

Foster told the court he may be a flawed man but claimed he was telling the truth and he would not wrongfully accuse a man of murder.

"He told me things that only he could know," Foster told the hearing.

Foster said Mr Chardon told him he had an alibi for the time of the killing but could not recall what it was.

"He [Mr Chardon] spoke of Novy as though she was the devil, a horrible mother, a loose woman, a money grabber — he never said a kind word about her," Foster said.

Last sightings of Novy Chardon

Ms Chardon was seen on security footage paying for fuel at a Coomera service station the night she vanished, on February 6, 2013, and was also seen at her home in Upper Coomera later that night.

Novy Chardon was seen at her home in Upper Coomera on the night she disappeared. ( Supplied: Queensland Police Service )

Her car was found near a train station in a nearby suburb five days later.

There have been several searches for the body of Ms Chardon, who is originally from Indonesia.

A property at Mount Nathan in the Gold Coast hinterland was excavated in 2014 where they found parts of a white ute, a model seen near Ms Chardon's abandoned car.

Security cameras also filmed Ms Chardon at a service station the night she disappeared. ( AAP: Queensland Police Service )

In January, a 3.6-hectare property in Advancetown in the Gold Coast hinterland was then searched by 50 State Emergency Service volunteers, including a home and dam, for Ms Chardon's remains.

Foster is currently being held in a New South Wales prison on unrelated charges but was ordered to appear in person for the committal hearing in Brisbane.

His decades-long list of criminal activity includes convictions for fraud over weight loss scams, money laundering and breaching court orders.

The committal hearing continues.