PORTLAND, Ore. -- Investigators on the case of missing Portland boy Kyron Horman said Wednesday they were shifting to a task force-style investigation.

Multnomah County Sheriff Dan Staton said they would be moving to that format, more like a business plan, to better utilize resources in the case. Shifted resources would also help maintain the effectiveness of the department in areas other than the Horman investigation, he said in a news conference Wednesday afternoon.

Staton said there had been significant movements in the 15-week investigation and there was a more defined scope, allowing them to not be as broad in their efforts. Investigators can now concentrate on their current course to support a theory of what happened to the boy. He said he had seen no evidence that indicated Kyron was not alive.

When asked if people would be shocked to find out what they know, Staton took a long silence.

I know I'm taking a long pause on that, I have to think through that answer. I think there are things that come out of this investigation that will surprise you, that you'll think about later on when it's over. We have a knowledge of things we don't want to know about ... of things we wish we didn't know, he added.

Raw video:Sheriff Kyron update Pt 1 |Part 2

He said investigators were focusing on selective targets in the case that would help support a conclusion. Investigators need to close off possibly dead end tips in the case Staton labeled frivolous.

Kyron disappeared from Skyline Elementary in NW Portland on June 4, sparking the largest search in Oregon's history. No suspects or persons of interest have been named the case.

Staton said he was briefed with details from prosecutors last Friday and felt comfortable proceeding on the course they were on.

Our resources are limited and so are Portland's. Eventually you have to reach out for support and help, he said.

I don't want the family to believe we are changing this investigation in any way, shape or form ... I think all the investigators involved believe there is going to be an outcome in this, Staton said.

A lot of the things we looked at or suspected we no longer look at, we no longer suspect them, Staton said, referring to more than 3,000 tips taken in the case. A number of the leads have been significant.

Staton said a big frustration was that all tips needed to be reviewed and documented, taking up a large part of their time.

There are so many elements in this I can't even begin to comment on, Staton said. To this date, I've had nothing that's come into me from ... detectives ... that would lead me to believe that we shouldn't proceed forward.

We have hit a critical phase, Staton said, adding that not going to a task force model would critically affect the department's functionality.

He emphasized that they were not scaling back or moving to a cold-case type investigation. The FBIwould remain active, along with Port of Portland Police, Portland Police, Fairview and Troutdale departments. Staton added that Multnomah County would play about a 30 percent role.

Possibly the end of the week or next week could see more details released as the task force consisting of between eight and ten members is in place.

Kaine Horman and Kyron's mother Desiree Young were set to appear on the Chicago set of the Oprah Winfrey show Thursday to tell their story.

An October 7 hearing is set for Kaine's divorce petition with Kyron's step-mother Terri Moulton-Horman. Terri has been a focus of investigators in the case and accused by Kaine and Desiree of concealing information.

Complete coverage: Kyron Horman case

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