Paper trails and phone calls helped authorities locate 30 people feared missing in the wake of the La Conchita landslide, but officials late Wednesday announced that as many as 20 people remained unaccounted for.

Ventura County Sheriff's Sgt. Ron Nelson said investigators Wednesday morning located five La Conchita residents previously feared missing, plus an additional 25 people who had connections to the area. Three of those found Wednesday turned up safe at a residents' meeting at the Ventura fairgrounds.

"I've heard a lot of cheers today," Nelson said, noting the relief of law enforcement officers as they continued to whittle down the list of the missing.

Estimates of the missing have varied widely since Monday afternoon. At one time, authorities said they were searching for as many as 40 people.

According to Nelson, emergency personnel began compiling a list of La Conchita residents soon after the landslide. Using county tax rolls, the Internet, interviews with neighbors and tips from relatives searching for family members, detectives from the sheriff's Major Crimes Unit developed a list of people who might have been in La Conchita at the time of the mudslide.

Because of the nature of the community -- the neighborhood is favored by people on the move, including tourists, Nelson said -- officials have been unable to get a firm handle on exactly how many are missing.

"We just don't know," Nelson said. "The numbers we're going to see over the next few days are going to go up and down."

Wednesday evening, as authorities announced they had located about 30 people believed missing, the Sheriff's Department posted a new list of folks who had yet to be accounted for.

Senior Deputy Eric Buschow said investigators depend on tips from family and friends and paper trails from documents such as rental agreements to track those reported missing. Buschow said authorities must make direct contact, either by phone or in person, with an individual before his or her name will be removed from the list of the missing.

"We're not just taking phone calls (from third parties) at face value," he said.

An emergency hotline has been established for La Conchita residents and their families to check on the status of friends and relatives. Those with connections to La Conchita are being asked to check the missing list and report the names of loved ones still alive and well, or of others who are indeed missing and should be added to the list.

Officials also want residents, including those who already have been contacted by authorities, to call the hotline and provide their names so a master list of survivors can be drawn up.

The hotline number is 654-3593.