Police close Jane Furlong murder mystery case

The two-year investigation into the unsolved murder of Jane Furlong has officially been wound down by police.

Operation Darlia, the homicide inquiry into the 1993 disappearance of the 17-year-old, will no longer be actively investigated as of June 30.

Furlong's remains were found buried deep beneath sand dunes at Port Waikato's Sunset Beach in 2012, 20 years after she was reported missing from Auckland's Karangahape Rd.

She had been due to give evidence in two trials, against a serial sex offender and in a gang-related court case.

Despite thousands of man hours and a $50,000 reward offered for information, police have been unable to make a breakthrough.

Police say the case will remain open, but all staff working in the investigation have been deployed to other duties.

Detective Inspector Mark Benefield, the officer in charge of the investigation, said the case will no longer be active unless new information is received.

"We have explored hundreds of theories and a number of leads and I am confident that, if we get the right information from the right people in due course, we will be able to tell Jane's family who was responsible for her disappearance and death."

Mr Benefield thanked everyone involved in the investigation over the last two years, and paid tribute to the media for keeping Furlong's story alive.

Police have informed Furlong's mother, Judith Furlong, of the impending wind-down last month.

The information hotline, 0800 675 263, will remain operational for a few more weeks.