Detective Inspector Scott Beard, one of Auckland's top investigators and the district field crime manager, has been overseeing the file on Kayo's death. The investigation, named Operation Net, remains open and active.
"A senior detective has been responsible for reviewing the investigation and dealing with any new information that comes in to the police," Mr Beard told the Herald.
"To date there has been nothing to advance the investigation."
He would not be drawn on the suspect list, details of any profiling done around the killer or the specifics of the investigation to date.
Mr Beard reasoned that it was not the right time for police to release more detail than they already had about Kayo's death.
"If we had some information that I thought would warrant the use of the media I would do so," he said.
Kayo came to New Zealand from Japan in 1997 and settled in Christchurch for a year, studying English and working at a restaurant. In September 1998 she decided to travel north.
On September 11, 1998 Kayo flew to Auckland. At 2.14pm she was captured by CCTV cameras getting off a bus and crossing Queen St. The grainy images are the last of Kayo alive.
She checked into the Queen Street Backpackers, telling them she wanted to stay three nights. Then she walked up two flights of stairs to room 25, put her bags on her bed and headed outside again.
Ten days later her body was found in a locked fire-alarm cupboard of a stairwell linking the Centrecourt and BNZ buildings in Queen St. Kayo was naked and her body decomposing.
Police were never able to pin down how she died, but it was clear she had been murdered.
Police have never commented in detail on the state Kayo was found in, saying there are things only police and the killer would know. In 2000 Detective Inspector Kevin Baker, who was running Operation Net at the time, revealed police had collected forensic evidence from Kayo's body.
Those items, which he would not identify, had not been tested at the time. Police wanted to hold off, fearing they might jeopardise their chances of a DNA extraction in the future with better technology.
If you have information on the murder of Kayo Matsuzawa in September 1998, or recall anything from that day that might help identify who killed her, contact the Auckland police on 09 302 6400 or Crimestoppers anonymously on 0800 555 111.
Police seek to close five cold cases
Cold case murders where bodies were found, but killers have not been identified:
*Elizabeth Marusich lived as a recluse and was bashed on the back of the head. The 69-year-old's decomposed body was found in the Auckland Domain in October 1995.
*Angela Maree Blackmore, aged 21 and 10 weeks pregnant, died from multiple stab wounds. Her partner, Laurie Anderson, found her on the kitchen floor of her Christchurch home on August 17, 1995.
*Kirsty Bentley, 15, disappeared on New Year's Eve 1998 near the Ashburton River bridge. Her body was later discovered in the Rakaia Gorge.
*Claire Hills was abducted as she drove to her job at the Auckland Airport McDonald's on April 28, 1998. She was burned alive in her car on Mangere Mountain.
*Lien Nguyen, a 35-year-old Vietnamese immigrant, was found by her husband on the living-room floor of their Otahuhu home on May 18, 1998.
