The case of missing Christchurch teenager Hayden Miles has become a homicide inquiry.
While police are still publicly calling the 16-year-old's disappearance a missing person's case, The Christchurch Star can reveal a parallel homicide investigation has been underway for days.
Detectives believe he has been killed.
The shift in police focus coincides with an ongoing detailed forensic search of a run-down house at 612 Cashel St, Linwood.
Hayden's blood has been found in the house.
The search was widened yesterday to all houses within 200 metres of the address.
The Star understands police are close to a major breakthrough.
Operation Hayden head, Detective Senior Sergeant Tony Hill, would not answer specific questions put to him by The Star late yesterday, and was conspicuous by his absence when a media conference was held at Cashel St.
That was led by the head of the search operation Senior Constable Phil Simmonds - further evidence of the two inquiries underway one homicide, the other a physical search for clues to Hayden's whereabouts.
Earlier in the day Detective Senior Sergeant Hill put out a written statement saying the forensic examination of Cashel St could continue for a further two days.
He said: "The size of the property and the multiple dwellings on the site have made this a slower process than initially anticipated.
"The investigation team is also continuing to speak to various people who have come forward during the inquiry.
"We are making good progress in establishing the events surrounding Hayden's disappearance.''
It is a major contrast to two weeks ago when Hayden's mother Jacqui Miles and aunt Sandy Ward fronted a news media conference organised by the police in a heart felt plea for information.
A woman at Ms Ward's home wouldn't discuss Hayden's disappearance. She told The Star police had told the family not to talk to the news media.
On a Facebook tribute page to Hayden, mother Jacqui posted yesterday: "love u and pray for u every day. miss u soo much. love mum xxxxxxxxxxxxxxxxx.''
Hayden has been missing since August 22.
There had been "mixed reports'' according to police that the youngster had been mugged shortly before his disappearance.
Hayden last spoke to his mother Jacqui from an unknown person's cellphone in the Linwood area before going to a friend's house on Cashel St on August 22.
That was the last time anyone has seen or heard of him.
But the rundown Cashel St property - which neighbours say is a well-known local 'tinny house' (where cannabis foils are sold) - was a hive of police activity yesterday.
While officers said they were inspecting up to 200 properties - including abandoned houses - within a 200m radius of the property as they looked for "anything that relates to Hayden'' who has now been missing for 109 days.
Yesterday, 612 Cashel St remained cordoned off with police tape. Private security guards patrolled its perimeter.
Specialist police have been paying particular attention to an area at the rear of the property which they have now covered with a large tent.
Rusting shopping trolleys, piles of rubbish, a police generator and halogen lights littered the yard.
All of the building's windows have been blacked-out in recent days for a luminol examination - the technique used by forensic investigators to detect trace amounts of blood left at crime scenes.
The luminol substance is sprayed evenly across an area and blood flecks are illuminated in a darkened room.
Police refused to comment about The Star revelations this week that blood has been found inside the property.
A spokesman said: "There will be no comment while forensic examinations are carried out.''
The police were also tight-lipped over the move to a homicide inquiry, with a spokesman saying: "We won't be making any further comment.''