Kyron Horman Update: Cops "Not Giving Up Hope" as Search Enters Fifth Day

PORTLAND, Ore. (CBS/AP) The search for Kyron Horman entered its fifth day Wednesday as searchers continued to work to find the 7-year-old boy who disappeared after a science fair at his elementary school in a rural area of Portland, Ore.

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The challenging search continues to focus on the city's metro area and the dense hilly terrain ardespite receiving tips from as far away as Washington state. At least one person was injured Monday on an embankment near a rural road and had to be taken away by ambulance.

Multnomah County sheriff's Capt. Jason Gates said at a press conference that although the sheriff's office will "continue this investigation until there's a resolution," he hopes to have the search concluded by the end of the week.

"I'm certainly not giving up hope," Gates said.

Gates also said that the case continues to be considered a "missing endangered child" investigation and has not been classified as a criminal case. Gates said that "when we have elements or specific information about this case that would lead us in a direction where there are crimes" the sheriff's office will begin a criminal investigation.

Kyron was last seen about 9 a.m. Friday, shortly after the boy and his stepmother attended a science fair at the school. She has told police that she last saw him walking down a hallway toward his second-grade classroom, wearing a "CSI" T-shirt and dark cargo pants.

PICTURES: Kyron Horman Missing

A search began after Kyron didn't return home on the bus, and it was revealed that he had not been in class all day. Kyron's parents say they were not notified by the school until they called the school looking for him.

Gates said nearly all of the students at the school have been interviewed, as well as the majority of the faculty and staff. He said that investigators "have no reason to believe this is anything but an isolated case," and that area families need not take extra precautions with their children.

Kyron's parents are expected to release their first statement sometime Wednesday, and Gates said that a sheriff's deputy has been with the family at all times. He added that the search effort, which includes 22 state, local and federal agencies, is approaching the largest ever conducted by the county.

Anyone with information on Kyron's whereabouts is urged to call the Multhnomah County Sheriff's Office tip line at (503)-261-2847.

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