California fire: Number of missing persons in Camp fire skyrockets to more than 1,000. How can that be?

The death toll from the Camp fire has jumped to 71. But, perhaps more alarmingly, authorities also dramatically increased the number of missing or unaccounted for to 631 Thursday and then more than 1,000 Friday.

Why the huge increase?

Authorities raised the tally after combing through 911 call logs and other reports generated at the peak of last week’s chaotic evacuation. Officials said the new number may include some people who were counted twice or others who may not know they have been reported missing. On Friday, officials said that there might be duplications on the list and that some of those listed might be alive but simply have not checked in with the people who reported them missing.

LIVE UPDATES: The latest on the California fires »

How is the missing list being processed?

Authorities admit it’s going to be a long process. Butte County Sheriff’s Department officials have fielded calls from across the country from people asking about loved ones, some of whom they may not have been in regular contact with for a long time.

Officials said they’ve been going through shelters and tent camps set up outside Chico to check evacuees’ names against their list.

The Sheriff’s Department also has posted a 14-page list of names and asked the public for help. The list includes the ages and genders of some of the missing; a few appeared to have only tentative name spellings.

“In an effort to better inform the public this list of reported missing persons is being provided. If you see anyone on the list who is no longer missing please contact us so their name can be removed. Staff working the Missing Persons Task Force can be reached at: (530) 538-6570, (530) 538-7544, (530) 538-7671,” the Sheriff’s Department said.

The department also is taking missing persons reports.

What is the timeline for a final accounting?

After the wine country firestorms last year, it took weeks to sort everything out. At one point, there were more than 900 people listed as missing from those blazes.

But authorities slowly whittled down the list.

In the end, more than 40 people died, while everyone else was accounted for.

The Camp fire is significantly larger, though, having leveled more than 10,000 structures and burned 142,000 acres.

RELATED: These are the victims of the California wildfires »

UPDATES:

8:40 p.m.: This post was updated with new numbers.