An intense search that includes the California National Guard is underway for two experienced hikers and their dog who have been missing since Tuesday when they failed to return from a three-day trip in the Stanislaus National Forest.
Rescuers from at least 11 agencies are traversing treacherous terrain in search of Modesto residents Donna Hallberg, 55, and Mark Smallwood, 59.
Four scent dogs and a trail dog were tasked with tracking the couple, who left Sunday for a hike on the Crabtree Trail to several lakes near the community of Pinecrest.
"Donna and Mark are experienced hikers who have hiked the trail numerous times in the past," the Tuolumne County Sheriff's Office said.
Helicopters flew over the massive wilderness Friday, looking for any signs of the hikers within the national forest's meadows, snowy valleys, creeks and steep granite bluffs, according to the sheriff's office.
There had been no signs of Hallberg, Smallwood and their black-and-white dog, Lulu. Their gray Chevy Tahoe remained parked at the Crabtree trailhead.
The couple had packed enough supplies and equipment to last for a three-day hike.
A friend of the couple called Tuolumne sheriff's officials on Wednesday afternoon, notifying them that Hallberg and Smallwood had not returned Tuesday as planned.
The pair have cellphones, but rescuers are unable to track them because of the lack of service in the area.
Anyone with details about the couple's whereabouts is urged to call the sheriff's office at (209) 533-5815.
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