Four years after 19-year-old Leo Lipp-Neighbours mysteriously disappeared from a Nelson flat, police have taken a significant step in searching three Blenheim properties.
It is the first active development made public since a review of the case that has failed to find Mr Lipp-Neighbours since he went missing on January 24, 2010.
A silver watch given to the student by his family on his birthday was at the centre of police raids trying to discover his fate.
Police seized computer equipment and other electronic items from one of three rental properties they searched in Blenheim last week.
Investigators were acting after they received new information about the case.
The police warrant says investigators were looking for a silver watch with an engraving that read: "Happy Birthday Leo love mum and family".
His mother, Charlotte Lipp, could not be reached for comment.
Police were also looking for vehicle parts of his distinctive orange Toyota Corolla wagon, which has never been found.
A man living at one of the raided properties says he is innocent and police have been supplied with false information.
Head of the investigation Detective Sergeant Mark Kaveney, of Nelson, said that police searched three rental properties in Blenheim last Tuesday.
Computer equipment, hard drives and DVDs were seized and would be forensically examined.
People living at the houses would not be interviewed until it was known whether the equipment contained any information useful to the police investigation, he said.
"We want to check emails, we want to check if anyone's been talking about Leo."
Mr Kaveney would not elaborate further.
"I'd like to have found parts of the vehicle or sufficient information to lead to Leo's location," he said.
"I wouldn't think we are any closer [to finding him] at this stage."
Last week's searches were a continuation of the investigative work police had undertaken over the last four years and were similar to a number of other searches they had conducted, Mr Kaveney said.
He said police were not giving up hope of finding Mr Lipp-Neighbours.
"We know that someone out there knows something. I just hope their conscience gets the better of them sooner rather than later and they come forward with that information."
One of the men living at the properties said that eight police officers from Nelson and Blenheim arrived at his house last week. They had a search warrant based on suspicion of manslaughter, murder and grievous bodily harm.
"I'm an innocent man; there is no possible lead to my house or property," 44-year-old Brendon Phillips said.
Mr Phillips said he had never heard of Mr Lipp-Neighbours other than seeing his face on a poster in the Blenheim police station. He was charged with cultivating cannabis.
Mr Phillips said he believed police had been given false information.
"This implicates me in murder. Here is an innocent man implicated."
The only charges he had ever received was disorderly behaviour for preaching the Bible, he said.
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Police did not initially think Mr Lipp-Neighbours' disappearance was suspicious, but the inquiry changed tack in September after a case review.
Police now say they have concluded his disappearance is the result of foul play.
Residents of another property allowed police to search their home voluntarily.
Mr Kaveney believed the people living at the homes were not
known to Mr Lipp-Neighbours.
Police were still receiving information from the public about Mr Lipp-Neighbours which was "very pleasing".
There were still sightings of his car that had to be checked, he said.
"I can't go into details until we've done that."
Friend Ben Clark, who was the last to see Mr Lipp-Neighbours, said it was good news police were still receiving leads from the public. He was unaware of the raids.
"Hopefully it turns out to be something."
Mr Lipp-Neighbours, a Canterbury University student, was last seen leaving Mr Clark's Watson St flat in Washington Valley.
He had been drinking with friends at a Nelson club earlier in the night.
His family, friends and volunteers made extensive searches, including using a helicopter, of Nelson, Marlborough, Golden Bay and Buller. They put posters, checked service station security video footage and created a website, leolippneighbours.co.nz.
A $50,000 Crimestopper reward offered in 2010 remains unclaimed and active.
Anyone with information that may be relevant to his disappearance can contact Nelson police, ph 03 546 3840. Information can also be given anonymously by calling Crimestoppers on 0800 555 111.
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