DAVISON TOWNSHIP (WWJ) – A search team of hundreds is combing the area around a Genesee County park, looking for a 9-year old boy who disappeared on Independence Day.

An AMBER Alert is in effect for Omarion Humphrey — who goes by the nickname “Mars.” The boy — who is severely autistic and does not talk — was last seen at the Callis Lake Recreational Complex, off North Gale Road between Davison Road and Court Street in Davison Township, at around 6 p.m. Saturday.

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Davison Township Police Chief Rick Freeman says the search is covering a wide surrounding area.

“What we’re doing is a massive coordination between law enforcement, both what I’d call professional and volunteer search crews, all working together right now,” Freeman said.

Search patty command center. (credit: Jon Hewett/WWJ)

Search patty command center. (credit: Jon Hewett/WWJ)

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

Freeman said they’re following up on several leads.

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“We have some tips but nothing’s come to fruition yet, so those are forthcoming at this point,” Freeman said. “We’re both doing some physical searches and some investigations to try to find this young man’s whereabouts.”

Authorities were trying to rule out the possibility  that Omarion, who lives with a foster family, may have been taken by his birth parents. Oakland County Sheriff’s officials say they were asked by  Genesee County to check two Pontiac addresses listed for the boy’s parents — but investigators didn’t find anything.

Omarion Humphrey  was last seen at this park. (credit: Jon Hewett/WWJ)

Omarion Humphrey was last seen at this park. (credit: Jon Hewett/WWJ)

Sunday night police K9 teams searched a creek and a dive team searched ponds as well as Lake Callis.

Police said searchers would be heading into the woods on Monday and that volunteers were welcome. Those who want to help are urged to dress appropriately for a hike, and meet at the command center set up at the Lake Callis Pavilion at 1152 N. Gale Road.

According to a post on the Davison Township Parks and Recreation Facebook page, the Lake Callis Recreation Complex will be otherwise closed until further notice to help facilitate search efforts.

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Anyone who may have seen this missing child is asked to immediately call 911 or the Genesee County Sheriff’s Office at 810-732-4720.