Yanfei Bao has not been seen since 19 July. Photo: RNZ / Nate McKinnon
As the time Christchurch woman Yanfei Bao has been missing spans one week, police say the dive squad has been deployed to assist.
On Wednesday morning, Detective Inspector Nicola Reeves said a number of searches for the 44-year-old mother are taking place across the city.
Bao is a real estate agent for Harcourts Wigram and was last seen door-knocking in the suburb.
"Ms Bao was last seen on Wednesday last week and an active missing person investigation remains ongoing," Reeves said.
"Search activities will be taking place today in and around the Halswell River, and the nearby area of Greenpark.
"The Police National Dive Squad have been deployed to assist the investigation team."
Photo: RNZ / Nathan McKinnon
Reeves said the dive squad are expected to begin searching in the water today, depending on water levels being at a safe level for staff.
"Residents in the Greenpark area can also expect to see a police presence in the area searching for Ms Bao.
"We are keeping an open mind as to where Yanfei is and what may have happened to her, but we do have grave concerns at this time.
"As such, we are considering all possible lines of enquiry and making every effort to locate her."
Reeves said a scene examination remains ongoing at Trevor Street property in Hornby.
The Trevor Street property being examined by police is for sale. Photo: RNZ / Nathan Mckinnon
A tent was erected at the address on Tuesday morning after being seized by police on Sunday.
The property is for sale and its owners confirmed to RNZ that Bao was meant to show a potential buyer through the house last week.
A man was arrested at Christchurch Airport on Saturday in relation to Bao's disappearance.
He appeared in the Christchurch District Court on Monday, charged with kidnapping. He was given interim name suppression and remanded in custody.
Reeves said police wanted to express their appreciation for the help the public has provided in the search for Bao.
"The investigation team has received a number of pieces of information and are working through each report.
"Every piece of information is valuable to understanding what has occurred since Ms Bao disappeared."
Reeves said police are continuing to seek any information the public can provide about a silver Mitsubishi sedan with the registration DPH101 between 19 July and 22 July.
"If you can help, please get in touch with police via 105, either by calling or going online using 'Update Report'.
"Please reference file number 230720/5911."
Police search the Halswell River. Photo: RNZ / Nathan McKinnon