Forensic investigations are continuing as police search for the body of missing Auckland woman Carmen Thomas.
On Tuesday, Bradford James Joseph Callaghan, 32, Ms Thomas's former partner, with whom she had a child, was charged in the Auckland District Court with murder.
Detective Inspector Mark Benefield says the investigation is continuing and he is not ruling out further arrests.
Search warrants have been executed at some businesses in Auckland and three vehicles have been seized.
Ms Thomas, 32, lived in Remuera and has not been seen since 27 June.
Police believe she was killed in her home in Ngapuhi Road in the suburb of Remuera on 29 June and that her body was dismembered and disposed of.
Mr Benefield says anyone who has information, including the whereabouts of her body, must come forward.
Investigations are centering on a construction site on Victoria Street in central Auckland.
It has been reported a high-tech camera was lowered into the drainage system at the construction earlier this week.
Police and ESR scientists are expected to continue a scene examination of what is believed to be Mr Callaghan's home in Sonia Avenue in Remeura over the next few days.
Ms Thomas' mother, Teresa Scott, earlier came to New Zealand from South Africa to help with the investigation.
Mr Benefield says he was the one who had to tell her about the arrest and their suspicions about her daughter's body.