The body of a woman believed to be missing hiker Lily Hooper has been recovered from bushland in NSW Southern Highlands overnight.

The body was airlifted from Nattai National Park on Thursday night after an extensive eight day search ended in the discovery of the body, NSW Police told The Nightly.

The force said a port-mortem examination will be conducted in the coming days to determine the cause of death and formally identify Ms Hooper.

An SES rescuer made the discovery about 11.30am on Thursday after hundreds of people joined a multi-agency search to find the 18-year-old when she vanished on August 12 after she set out that morning on a hike.

Initial reports from rescuers led to confusion about Ms Hooper’s condition, which resulted in the teen’s parents being incorrectly told she was alive despite her body being found.

It wasn’t until after an “eight to 10 minute period” her parents were given the correct information that their daughter was deceased, police said.

In that time, NSW Premier Chris Minns relayed the incorrect update in a budget estimates hearing after receiving the wrong details.

Assistant Commissioner Joseph Cassar said it was not just the Premier who had been delivered false information, but Ms Hooper’s parents, too.

“The initial information that the searchers believed she was alive and that was communicated (to the parents),” he said.

“But within eight to 10 minutes we were able to give them an update.”

Ms Hooper’s cause and time of death has not yet been determined and will form part of the investigation.

When asked what Mr Cassar’s message to the parents was regarding the miscommunication, he did not apologise.

“I think the only thing I can sincerely say is - my absolute condolences go out to Lily’s mum and dad,” he said.

“Everyone of the investigators and the searchers, whether the volunteers or head personnel, hoped for a more positive outcome.

“I can tell you the police that were in charge at the time had spoken to her mum and dad, certainly hoped for a positive outcome.

Later on Thursday afternoon, NSW Police Commissioner Mal Lanyon apologised to Ms Hooper’s family for the miscommunication.

“I unashamedly apologise for any additional trauma that may have caused Lily’s family,” he said.

“But certainly for the embarrassment and confusion that caused the miscommunication, obviously was born out of elation that Lily had been found.

“And certainly those at the command posts relayed, tragically, that miscommunication then led to a deflation, and obviously we know now and impact on her family.

“Once again, I unreservedly apologise for that miscommunication.”

Ms Hooper was last heard from when she reached the summit of Bunnum Pic around mid-morning on August 12.

That evening, the experienced bushwalker did not return and could no longer be reached, prompting a multi-agency search for the teenager.

Ms Hooper’s car was found at the Bonnum Pic trailhead on Wanganderry Road around 11pm but no further signs had been found of her.

Mr Cassar said the body was located “some significant distance” from where the car was found.

He added that “it wasn’t on a clear, walkable track”.

The Assistant Commissioner said he was “not aware who informed the Premier” of the update on the search.

Mr Lanyon said the Premier had apologised to him.

“The miscommunication obviously went through policing commands and up to government and has been reported widely,” he said.

“It was something that was inadvertent, but as I said, was borne out of looking to find Lily and bring her back to her family.

“It goes through a range of police commands to the minister for police and then to the Premier’s office.”