Hundreds of people are still listed as missing four days after wildfires ignited and zipped through California wine country, and the search for them has been marked by confusion and responses that differ dramatically by area.

Authorities in hard-hit Sonoma County are searching for those reported missing by family and friends, but many of them live in fire zones that can't be accessed as the flames rage largely out of control. The wildfires ripping through Northern California have killed more than two dozen people and burned thousands of homes and businesses.

About 400 people are listed as missing, Sonoma County Sheriff Robert Giordano said Thursday, although those numbers may include duplicates or people who are actually safe. His department has more than 20 detectives and other personnel working most of each day to investigate the reports. He also has held several press conferences a day to update the numbers of reported missing.

Napa County Sheriff John Robertson, on the other hand, has urged people to mark themselves as "safe" on an American Red Cross website so family and friends won't worry. His agency isn't releasing the number of missing reported. With authorities focused on getting people out of the way of flames much of this week, friends and relatives desperate for news turned to social media for help and checked shelters and hospitals in person. Others worried from afar.

A Utah woman is puzzled that it appears her mother safely evacuated her Santa Rosa house on Tuesday but has not been heard from since.

Sheriff's deputies on Wednesday visited the home of Norma Zarr, 61, finding no damage and her silver Honda CRV gone. "I don't know if she's under a rock or if she's OK," Charlene Baumunk Allen said. "This is a trying time."

Jeannette Scroggins, on the other hand, received the worst news possible. Sheriff's deputies found the body of her aunt Karen Aycock, 54, on Thursday. Aycock's family has been looking for her since Monday when her home in Santa Rosa was destroyed, Scroggins said.

Deputies prevented family members from searching Aycock's house because of fire danger.

Scroggins says her aunt lived with seven to 10 cats and her body was found near a bathroom in the back of the home. "This is so terrible," she said.

Others found loved ones safe.

Family and friends could not reach Rick and Leslie Howell for a day, a common occurrence amid the chaos and lack of communications. They don't own mobile phones and both fled with little notice ahead of flames that destroyed their Santa Rosa home. They were found Wednesday after fleeing the day before.

Several dozen names were on a dry-erase board at the Finley Community Center in Santa Rosa, which the Red Cross had turned into an evacuation center with dormitories, cold showers and three meals a day.

Dozens of evacuees hung about, waiting for word for when they could return to their homes. Debbie Short, an evacuee staying at the Finley Center, had been listed as missing. She was walking past the dry-erase board when she noticed her name on it, likely because a friend had been looking for her.

A Red Cross volunteer erased her name.