A 57-year-old man has been arrested in connection to the Bridget Simmonds missing persons case, after the remains of a body were found in Northland on Friday.
The man has been taken into custody after being charged with assault on an unrelated matter, but police say the won't rule out further charges.
They are not looking to arrest anyone else related to the case.
On Friday, police said while the formal identification process of the body has not yet been completed, they have reason to believe it's Simmonds.
A series of search warrants have been carried out at rural properties in Parakao this week, and the site of interest was excavated on Friday after police learned Simmonds may be buried there.
About 50 staff - including the Police National Dive Squad, Police Specialist Search Group and a Search and Rescue team - were involved in the searches, police say.
Detective Senior Sergeant John Clayton says as well as the remains, they have found some items of interest at the property.
A scene guard will be in place at the site overnight.
Detective Senior Sergeant John Clayton says while the outcome is a tragedy for Simmonds' family, he hopes it'll provide the closure they’ve been looking for.
"Bridget was a loved mum, sister, daughter and friend and our heartfelt sympathies and thoughts go out to her family. We have been in contact with them and are ensuring they get the support they need."
Simmonds was reported missing on March 6, 2019, 11 days after being dropped off by her mother at the Regent Countdown in Whangārei.
On Wednesday, Det Snr Sgt Clayton revealed the death was being treated as suspicious after new evidence from the public.
He said they had "grave concerns" something sinister had happened to Simmonds.
In April, Simmonds' mother Carol issued a plea for the public to help her find her daughter.
"Bridget, everyone is so worried about you and we have all been searching for you," her family said in a police statement.
"This is not like you to be out of contact this long, your children miss you and want to hear from you - we love you and miss you."