More than 30 search-and-rescue units and 10 dogs from the San Mateo County Sheriff’s Office and California Highway Patrol were dispatched at 3:50 p.m. Wednesday afternoon after police received a phone call from a resident who said she heard a dog whimpering inside the canyon at Vista Park, said Sgt. Ron Albertson of the San Carlos bureau of the Sheriff’s office.

“We have no proof there is even anybody missing at this time,” said Albertson. ‘We have no missing person report, no vehicles parked along the street near the park, nothing. We are continuing the search at this time.”

Contrary to some media reports, police said there are no official reports of someone yelling for help from the canyon.

When the deputies arrived they called out into the canyon and heard only the sound of what could have been a whimpering dog. The Sheriff’s office airplane was dispatched around 4:20 p.m. and circled the perimeter while search dogs scoured the canyon.

Albertson said one dog came upon a scent from one area but nothing was located.

As the night approached and darkness settled in over the park, CHP searched the area with a helicopter and heat-seeking equipment to no avail. Police said the search became difficult in the darkness due to the heavy brush and absence of any light in the area.

“We discontinued the search around midnight because it was too dark and the brush too heavy,” said Albertson. “We picked the search up again this morning.”

The San Mateo County Sheriff's Office provides police services for San Carlos.

Anyone with information on the Crestview Park incident is asked to call the sheriff's office at (650) 363-4911.