Crews are searching for a missing hiker in the canyons of the San Bernardino National Mountains.

Neighbors say they last saw 35-year-old Tony Jacquet on Monday afternoon walking with his dog in Forest Falls.

The dog returned home later but Jacquet did not.

Sheriff's officials say Jacquet has a medical condition that causes seizures and needs to take medications daily.

Search crews and dog teams have been joined by a helicopter.