DAVISON TWP. (WWJ/AP) – After four days of intense searching, the mass rescue operation aimed at finding a missing 9-year-old autistic boy has been called off.

Davison Township Police Chief Rick Freeman made the announcement Wednesday night, thanking the countless volunteers for their efforts in trying to find Omarian Humphrey.

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“All this means is that the large-scale, visible, tactical searches that you’ve seen to this point, the first several days that included all the volunteers and whatnot, we’re calling back,” said Freeman.

An Amber Alert for Omarian remains active.

Omarion Humphrey (Handout photo)

Omarion Humphrey (Handout photo)

Hundreds of law enforcement officials and volunteer searchers have been scouring a 5-mile radius in and around Lake Callis Recreation Area, near Flint, where Omarian was last seen on Saturday during a Fourth of July gathering with his foster family.

Police on Wednesday asked volunteers to stay away from the park so trained professionals could search the grounds. Despite a crew of about 800 people, including 60 to 80 police dog units, searchers turned up few clues.

“Obviously since we have not yet found Omarian, this investigation is far from over,” said Freeman. “My staff will, of course, continue this investigation and we will hit any hot spots, follow any tips until we get the resolution that we want.”

Authorities have kept the park’s splash pad, pavilion and ball fields lit at night and music has been playing in hopes of coaxing Omarion from hiding if the boy still is in the area. Authorities have said he may not speak but answers to the name “Mars.”

“We’ve used techniques that you almost think would be silly in some investigations,” Freeman said. “The experts are telling us these are little things – anything we can grab at that might attract his attention.”

Omarion’s biological father, Jamell Humphrey, said his son was terrified of the water.

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“You know, autistic children and water just don’t mix,” Humphrey told WWJ’s Jon Hewett. “So I automatically thought that he was in the water. And so for the first two days when they were searching that water, I mean, my heart was all over the place.”

The boy’s birth mother, Khisha Humphrey, has said she no longer believes Omarion is in or near the park.

“I think someone probably took him and they (foster parents) were not watching,” she said.

Khisha Humphrey said Omarion is one 11 of her children taken earlier this year by the state because she didn’t have adequate housing. She said the state is partially responsible for her son’s disappearance.

“They failed miserably and they know it,” she said. “There’s no way — they’re saying that he needed to be in care somewhere else but they lose him. You trusted somebody to lose him.”

Police have no evidence Omarion was abducted, but that’s not being ruled out, Freeman said. Relatives of the boy have been questioned, and their homes and vehicles searched.

In the meantime, Jamell Humphrey said he just wants to wake up from this nightmare.

“Will they find him? I don’t know. I hope so,” he said.

Omarion is about 4-feet tall and 70 pounds with black hair and brown eyes. He was last seen wearing only black shorts with a thin, red stripe — no shirt and no shoes.

Anyone who thinks they’ve seen Omarion should immediately call 911. Anyone with other information is urged to contact police at 810-732-4720.

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