As the anniversaries of Leo Lipp-Neighbours' disappearance came and went, family and friends spoke of the pain of not knowing his fate.
New information from the public and a renewed police investigation are finally bringing them closer to finding out.
Police yesterday made a startling announcement in the cold case, saying they believe "someone committed a serious crime" against Mr Lipp-Neighbours who was 19 when he disappeared from his Nelson flat on a summer night in 2010.
"That person must be held to account," Detective Sergeant Mark Kaveney, of Nelson CIB, said.
Nelson man Ben Clark, who was Leo's flatmate at the time, said yesterday he was struggling to comprehend the idea someone could have killed the "quiet, smart" teenager.
"I don't choose to believe that. I don't want to believe that," he said.
"I'd rather believe he's driven off the road and we hadn't found him, than someone hurt him."
Mr Lipp-Neighbours, who was studying engineering at Canterbury University, was staying with Mr Clark during the holidays when he disappeared in the early hours of Sunday, January 24, 2010.
He had been drinking with friends at a Nelson club earlier in the evening before driving away from Mr Clark's Washington Valley flat in his distinctive orange Toyota Corolla stationwagon.
He told a friend he wanted to be "at one with nature".
Mr Clark said a detective visited him about a month ago saying they were looking into it with "fresh eyes".
He told the Nelson Mail he hoped that police would reach some kind of conclusion about what happened.
But he was not confident unless someone came forward.
"I thought something would come up a lot earlier if it was going to, but who knows?"
Mr Clark was part of the intensive search effort in the three months after Mr Lipp-Neighbours disappeared.
Only yesterday, Mr Clark had driven up to a quarry in the Maitai Valley to search - a spot he had also searched previously with Lipp-Neighbours' father, Colin Neighbours.
Mr Lipp-Neighbours was not someone who would have enemies, Mr Clark said.
"Everyone liked Leo. He was such a good guy. He was really quiet, wasn't in your face, really smart."
Mr Clark wondered if it could have been a case of "wrong place, wrong time", but said he never felt unsafe living in the area.
Though more than three years had passed since his friend went missing, he was "always there with us, in our minds".
Another friend, who did not want to be named, said the passage of three-and-a-half years had not dimmed the tragedy.
His friend's disappearance was on his mind a lot, he said.
Mr Lipp-Neighbours' mother, Nelson painter Charlotte Lipp, she did not want to comment on the latest development because it was a police matter.
Mr Kaveney said information received from the public led police to conclude that the teenager's disappearance involved foul play.
He would not elaborate on the nature of the new information but said the conclusion followed a detailed 10-month review of the case.
Police issued a nationwide appeal yesterday for anyone with further information to come forward, and reiterated that a $50,000 reward from Crimestoppers was still available.
Police will be putting up new posters around Nelson asking the question: "Do you know how is responsible for Leo's disappearance.
"It's time to speak up now."
Mr Kaveney said police were continuing to receive a constant trickle of information from the public and that had built a picture "that led the investigation team to the conclusion that the disappearance now appears suspicious.
"We are speaking with a large number of people and we believe there are other people in the Nelson community who know exactly what has happened.
"It is time now for those people to come forward, tell us what they know, and enable this matter to be brought to a conclusion."
Mr Kaveney said police had remained in contact with Leo's family since his disappearance and he would dearly like to get them some answers.
On the third anniversary of her son's disappearance in January this year, Ms Lipp said the family still did not know anything.
"We think that we've lost Leo, and that we may not find him, and we have to accept that. That doesn't mean we will ever stop wanting to know what has happened to him.
"Until we know, we have to have an open mind, and we'll keep on trying to find out."
In 2010 Crimestoppers offered a $50,000 reward for information leading to the location of Mr Lipp-Neighbours and his vehicle. That reward is still in place with Crimestoppers determining the amount to be paid.
Anyone with information that may assist the investigation can call Nelson Police, 546 3840.
Anonymous information can be given by calling Crimestoppers 0800 555 111.
HOW EVENTS UNFOLDED
January 24, 2010: Nelson student Leo Lipp-Neighbours, 19, who had been out with friends at a Nelson club, is last seen in his distinctive orange Toyota Corolla station wagon at 4am driving away from a Washington Valley flat. A missing person investigation is launched by police.
January 28: Police follow up on a reported sightinag of Mr Lipp-Neighbours, but still hold grave fears for his safety, saying his disappearance was out of character and they have concerns about his state of mind at the time he left his flat.
January 30: Mr Lipp-Neighbours' family hire a helicopter to search for him, and scour roads for any sign of his car. They are worried he may have lost control while driving on a remote road.
February 1: Mother Charlotte Lipp issues a tearful plea for information on her son's whereabouts. More than 30 friends and helpers search Queen Charlotte Sound, Golden Bay and St Arnaud, Murchison and Lewis Pass. By this time three helicopter searches have also been made.
February 13: Friends describe Mr Lipp-Neighbours as being in a "dark" mood on the night he went missing.
February 17: The Wakapuaka sewage ponds are searched for any trace of Mr Lipp-Neighbours or his car.
February 24: Police move their search focus to the Marlborough Sounds, in and around Port Underwood.
March 20: Search and Rescue volunteers search the Whangamoa area.
June 12: Mr Lipp-Neighbours' friends reveal his last words before he disappeared were: "I'm going to be at one with nature."
January 22, 2011: A year on from the disappearance, the case suffers from a complete lack of leads. Police appeal to the public to come forward with more leads.
June 29: A $10,000 reward for information on Mr Lipp-Neighbours increases to $50,000.
January 21, 2012: On the second anniversary of his disappearance, Mr Lipp-Neighbours' parents again call on the public for information, saying their intuition leads them to believe he died shortly after he went missing, but that they remain hopeful.
January 24, 2013: On the third anniversary, police say they have not ruled out foul play in Mr Lipp-Neighbours' disappearance, with a detective saying he believed there were people in the community who knew more than they were saying.
September 6: Police announce they believe someone had "committed a serious crime" against Mr Lipp-Neighbours.
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