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PLEASANTON, Calif. - An extensive search is underway on Sunday in Pleasanton Ridge Regional Park, where authorities are looking for a man who didn't return from a run Saturday in the hills.
Philip Kreycik, 37, parked his car near the Moller Ranch staging area about 11 a.m. and told his wife he was going for an hour-long run in the East Bay Regional Park, Pleasanton police said.
Kreycik's wife reported him missing at 2 p.m. Saturday.
"He had planned it out on that app so we knew where he was planning on running and that was the basis for our initial search. We've expanded that search to complete the entire park," Lieutenant Chris Niederhaus with Pleasanton Police said
Kreycik tracks his frequent long runs on an app connected to a wearable fitness tracker. But his run on Saturday didn't get recorded, and police are unable to pinpoint his location because his phone was left inside his car. His wife allowed police to access his phone.
Kreycik planned to run six to eight miles, according to police.
"Among runners, if we're only going to go out for an hour, we don't think anything's going to go wrong and why bother carrying it if you can drop it and break it?" Tyler Wolfe, a running buddy of Kreycik who spent five hours on Sunday searching for him in the off-trail brush, said.
'He's a hearty runner, got a lot of experience, and a lot of off-trail knowledge," Wolfe said.
Volunteers, some who knew Kreycik, and dozens more in the running and hiking community who saw a post about the search for Kreycik on Facebook, joined the search effort Sunday.
"I believe easily 30 to 50 should be here right now," Arun Sharma, one of the volunteer searchers, said.
Kreycik is described as White, with a thin build and brown hair and eyes. He is presumed to be wearing running attire.
Kreycik is an avid distance runner with no known health conditions, police said.
Pleasanton police officers and personnel from East Bay Regional Park police, the Alameda County Sheriff's Department and the California Highway Patrol are using drones, fixed-wing aircraft, off-road vehicles, and search and rescue teams to locate Kreycik.
"Something where they've gone missing and we've done this extensive of a search and not found them is new to us," Niederhaus said.
The park remains open for visitors, police said.
Anyone with information about Kreycik's location is asked to contact the Pleasanton Police Department at (925) 931-5100.
"We're still hopeful," Niederhaus said, "but we're starting to do repetitive searches at this point."