Overseas associates of missing man John Beckenridge talking to NZ police

Overseas associates of missing man John Beckenridge, who abducted his 11-year-old stepson last year, are working with New Zealand police to track the pair down.

Overseas associates of missing man John Beckenridge, who abducted his 11-year-old stepson last year, are working with New Zealand police to track the pair down.

Swedish-born helicopter pilot Beckenridge broke a court order on March 13 last year by picking up Mike Zhao-Beckenridge from his new Invercargill school.

The pair, who by all reports enjoyed a close relationship, camped at various places in the Catlins before Beckenridge's dark-blue 4WD Volkswagen Touareg went off a 90m cliff near Curio Bay a week later.

It took police six weeks to recover the battered wreck from the treacherous waters and there was no sign of any bodies.

On the one year anniversary of their disappearance, police said there was no evidence of the pair leaving the Catlins area.

Many locals, and friends and neighbours of Beckenridge, believe that Beckenridge staged their deaths and that they are now hiding out either in New Zealand or overseas.

Missing boy Mike Zhao-Beckenridge. Photo / supplied

But there have been no reported sightings since they were seen at Tokanui garage on March 17.

Detective senior sergeant Stu Harvey has told the Herald that the police inquiry still live.

He confirmed that "associates of Beckenridge who live overseas" are now helping police with inquiries.

But he referred to say who they were or how they are helping the police case.

Border alerts remain in place at New Zealand ports, while Interpol is still helping New Zealand investigators.

In March, Harvey said there had been a "major time lapse" in getting information back from overseas agencies.

Nine months on, and police are still waiting.

"We are still waiting for some overseas enquiries to come back," Harvey said.

Police are treating it as missing persons case.

Mike's mother Fiona Lu has repeatedly declined to comment publicly.

Harvey said earlier this year that she has been frustrated at the lack of concrete leads for police.

Over the past year, police have received multiple sightings of the pair reported to them by members of the public across New Zealand, including Southland and Canterbury.

However, the potential leads never amounted to anything.

The police file has not yet been passed over to the coroner.

"Once all enquiries are concluded, the file will be reviewed and a decision will be made on the next step in the process," Harvey said.

He earlier said police are "keeping an open mind to what's actually happened to them".

"We've spoken to a lot of people, and a lot of friends, associates of John Beckenridge," Harvey said in March.

"There has been no information at this stage that we have that would suggest that... somebody is helping them."

Beckenridge, who was living in an upmarket Queenstown estate before disappearing, was well-known in Papua New Guinea flying circles.

Pilots recall an experienced, talented and popular commercial pilot, who is also flew in Afghanistan and is believed to have several aliases, including John Locke, John Robert Lundh, Knut Goran Roland Lundh and John Bradford.

Pacific Helicopters PNG chief executive Mal Smith, his former boss who has been interviewed by New Zealand police, said he knew Beckenridge had been having "problems getting access to his kid but we didn't know it was to that extreme".

Aviation expert Peter Clark has said it would be "improbable but not impossible" to flee New Zealand by helicopter.