Police have yet to formally identify the body but said several people were helping with their inquiries.

Officers said they found the body during a line search of grassland at Majura on Thursday afternoon and had treated the death as suspicious.

Audrey Carville, who lives on the NSW Central Coast, said detectives had told her they thought the body was her 52-year-old son as his clothes appeared to match a description given to police.

An autopsy would be carried out this weekend and family members were told they might need to provide DNA material to help with the identification.

"It's shocking. We're just shocked," Mrs Carville said.

"We just can't bring our minds around it.

"I keep saying I hope it isn't him but they're pretty certain it is."

Last week, Mrs Carville told Fairfax Media she received a bizarre phone call the morning after her son, who worked as a public servant, disappeared.

"I rang his phone three or four times but nothing so I rang one of his friends and he hadn't seen him," she said.

"I rang another of his friends who was just coming home from work and he hadn't seen him so he went around after work. He said the door was open and his wallet and everything was on the table."

The ex-partner of Mr Carville's brother, Adrian, is understood to have been the last person to see him at his Evatt home at 9.30pm on November 4.

That was also the last day his mother spoke to her son, who was the second eldest of four boys, over the phone.

"I never heard from him again," she said.

His other brother's wife, Kathy Carville, described him as "110 per cent dedicated to his family life".

"He puts others before himself, which is a really bad trait that he has because he doesn't think about himself," she said.

Audrey Carville said police "haven't said a thing" to her about details of the investigation and told her they wanted to first make sure the body was that of her son.

"They said whoever's done this, we will catch.

"It's affected my youngest son really badly because they used to live together."

The body was removed from bushland overnight and forensic experts were still working to confirm the cause of death.

It is understood the body was found on defence land in the area. Police have not publicly confirmed even the gender of the body.

Police remained tight-lipped on the investigation but on Friday revealed there were "firm links" between Mr Carville's disappearance and a vehicle dumped in the Molonglo Gorge.

Earlier this week, police appealed to the public to help locate the driver of a Toyota Landcruiser found crashed in heavy scrub.

A tip-off from a person who saw the vehicle in Majura on November 12 sparked a sweeping search of the area before the body was found.

Police said the body might be able to be formally identified after an autopsy was carried out during the weekend.

Detective Superintendent Paul Shakeshaft hoped the autopsy would also help to determine when the victim died and how long the body had been in the area.

He urged anyone who had information that could help police track down the killer to come forward.

"You may think that the information you have is irrelevant, however it may just be the missing piece in the puzzle that we need to solve this investigation."

Detective Superintendent Shakeshaft said the probe was in its early stages and he would not be drawn on whether any suspects had been identified or interviewed.

"We have a number of lines of that we are pursuing and we will see how those develop over coming days."

No arrests have been made.

Detective Superintendent Shakeshaft said the incident was distressing for Mr Carville's family and homicide detectives would continue to keep them abreast of any developments.

The incident also was "not pleasant" for the territory's police officers and their welfare was "paramount", he said.

The death is the fifth homicide in the ACT in 2015 after the capital was rocked by the deaths of one man and three women earlier this year.

Each of those alleged murders was linked to family violence.

Anyone with information that could assist police to contact Crime Stoppers on 1800 333 000, or via act.crimestoppers.com.au.