EL PASO COUNTY, Colo. — The search for 11-year-old Gannon Stauch, who has not been seen since Jan. 27, moved into southern Douglas County, according to a tweet from the El Paso County Sheriff's Office (EPCSO)

The agency said Wednesday that they were searching areas in Northern El Paso County and southern Douglas County to follow up on leads in the case.

More than a dozen other agencies have joined the search, including Douglas County Search & Rescue -- which had 12 people conducting an “outside search” near Highway 105 between Palmer Lake and Larkspur.

Letecia Stauch, who is Gannon's stepmother, told investigators she last saw Gannon at his home in Lorson Ranch between 3:15 p.m. and 4 p.m. on Monday, Jan. 27. She told the El Paso County Sheriff’s Office (EPCSO) Gannon said he was going to a friend's house. No one has seen him since. 

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However, on that same day, a neighbor captured surveillance video, which appears to show Gannon getting into a truck. The neighbor told KRDO, our sister station in Colorado Springs, the truck belongs to Letecia Stauch. Investigators with EPCSO haven't commented on the video except to say it's part of their investigation.

Last Thursday crews returned for a second time to search Johnson Reservoir, which is not far from the Stauch family home. The second time, a submersible remotely operated vehicle equipped sonar was used to search the water

RELATED: Crews search reservoir near home of missing 11-year-old Gannon Stauch

Anyone with information on his whereabouts is asked to call the EPCSO tipline at 719-520-6666 or email tips@elpasoco.com.

A week ago, Gannon's parents released a video statement through EPCSO. In it, they described their son as energetic and happy and said he loved sports. They also urged anyone with information to come forward.

"I don't even have answers for my feelings, other than I'm afraid," said Landen Hiott, Gannon's biological mother. "Afraid that I will never hear his voice, that I will never hear him run and say, 'Mommy!', that I will never hear those corny jokes that he always tells. I am afraid I will never see that again or hear it. I don't want to believe that because that means I'm giving up hope, and I'm not giving up hope."

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