A man found injured on the side of Porter Creek Road north of Santa Rosa early Friday morning had been stabbed multiple times, emergency medical personnel said.

Sonoma County sheriff's detectives are investigating the case as an attempted homicide, sheriff's Lt. Dennis O'Leary said.

The victim had "significant injuries that could have been life threatening," though he now is expected to survive, O'Leary said.

Detectives had not been able to confirm his identity, however, and he had not been available to be interviewed because of his condition, O'Leary said.

O'Leary said the victim was being treated in the intensive care unit of a local hospital.

A passerby found the man on the shoulder of the road near the Mark West Springs Lodge and Leslie Road shortly after 1:30 a.m., O'Leary and emergency dispatchers said.

The woman called 911 but was quickly joined by an ambulance crew that came upon the scene while transporting a patient from Lake County to a Santa Rosa hospital, O'Leary said.

Medics aided the stabbing victim until another ambulance arrived to take over and get him to the hospital, O'Leary said.

Detectives were combing a stretch of Porter Creek Road Friday for evidence.