Speaking outside the property today, Mr Hill said: "We know this was the last address where Hayden was known to have been on August 22.
"Our enquiries so far indicate that some sort of incident has occurred at this address and we are now focusing on this location to get a better picture of what has happened here.''
The officer refused to "speculate about what has happened,'' adding that the inquiry is still "very much a missing person investigation, as Hayden has not yet been located.''
Christchurch police forensic staff and ESR examiners will be at the site for at least three days.
People living at the address, who are not known to Hayden, have been fully cooperative with police, he said, and alternative accommodation is being arranged for them.
Hill refused to confirm reports from local residents that the property was well-known to police.
But he added: "There was a person associated with Hayden living here and we know Hayden came here on that night.''
When he phoned his mother that night - the last time she has heard from him - he was "clearly upset he had his cellphone taken off him.''
He also refused to say if Hayden had been injured in the incident as police had received "mixed reports''.
Hill said: "Definitely someone out there holds the key to this investigation and we want them to come forward and tell us what they know.''
Police confirmed that Hayden's family has been briefed on the latest phase of the investigation, and police family liaison staff are continuing to support the family.
One of Hayden's friends, 18-year-old Lisa Kenyon turned up outside the property during the press conference today after reading online newspaper reports that it was being forensically examined.
The unemployed woman said she was starting to "think the worst'' since it is more than three months since anyone has heard from the missing boy.
Ms. Kenyon said: "I'm quite worried now and starting to think the worst. It's been a long time. I've been a runaway kid before and I could only last a couple of months before I came home.
"It's pretty out of character for him. And it's weird for him not to be in touch at all, not even to go onto facebook or whatever. None of us have heard anything from him.''
Hayden's family is desperate for a positive break.
They have been dropping leaflets in Linwood, Hornby, Aranui, Bishopdale and Burnside, the areas where Hayden grew up, asking for help.
His mum Jacqui Miles said last week: "Hayden's lack of contact with his family is totally out of character, and very concerning to us. We are aware that most missing people are found within 48 hours and as time goes on our fears for his wellbeing have grown.
"We believe that someone will know what has happened to Hayden and we are asking them to come forward and help the police with their investigation. With Christmas approaching, we would dearly love to have our Hayden home with us soon.''
