Searchers are continuing to comb the wooded hills near Hopland for a man who disappeared after taking his dead, 5-month-old son to a Ukiah hospital.

"So far, we're unable to locate him," Ukiah Police Chief Chris Dewey said late Friday afternoon.

Casimir George Janusz, 36, of Ukiah, brought the unresponsive boy to Ukiah Valley Medical Center at 9:26 a.m. Wednesday, according to Ukiah police.

After it was determined the boy was dead, Janusz left the hospital without explanation, police said. The cause of the child's death has not been determined.

After leaving the hospital, Janusz apparently drove to his family's ranch in Hopland, where he abandoned the vehicle and disappeared, police said.

Searchers on Friday included officers from the Ukiah Police Department, Mendocino County Sheriff's Office and Sonoma County Sheriff's Office, which provided a helicopter, Dewey said.

He asked that anyone with information about Janusz' whereabouts call 463-6262.