Around 631 people are missing and at least 63 are dead after the wildfires that have devastated Northern California, authorities have confirmed.
The number of those unaccounted for has jumped dramatically following a news conference delivered by Butte County Sheriff Kory Honea.
Just a day earlier the figure stood at 130 missing, while an estimated 52,000 people have been displaced and more than 9,500 homes have been destroyed.
Mr Honea said authorities had gone back through all emergency calls and other reports of missing people from the past week to come to the new number.
The figure could include some who have fled the blaze and may not realise they have been reported missing, he added.
“The chaos that we were dealing with was extraordinary,” he said.
“Now we’re trying to go back out and make sure that we’re accounting for everyone.”
Authorities also confirmed another seven fatalities, this brings the death toll to 63, making the blaze the deadliest wildfire in state history.
A decade ago, as two wildfires advanced on the town of Paradise, residents got stuck in gridlock traffic. That led authorities to devise a staggered evacuation plan, which was employed as the fires struck again last week.
Despite the strategy, Paradise’s carefully laid plans quickly devolved into a panicked exodus.
Some survivors said that by the time they got warnings, the flames were already extremely close, and they barely escaped with their lives. Others said they received no warnings at all.
A British father living in Paradise told Yahoo News he only escaped with his wife and five-month-old baby after receiving a warning text message from a friend living nearby.
Now authorities are facing questions over whether they took the right approach.
Reeny Victoria Breevaart, who lives in Magalia, a forested community of 11,000 people north of Paradise, said she could not receive warnings because mobile phones were not working.
She also lost electrical power.
Mr Honea said evacuation orders were issued through 5,227 emails, 25,643 phone calls and 5,445 texts, in addition to social media and the use of loudspeakers.
As mobile phone service went down, authorities went into neighbourhoods with bullhorns to tell people to leave.
“The fact that we have thousands and thousands of people in shelters would clearly indicate that we were able to notify a significant number of people,” the sheriff said.
More than 450 rescue workers have been assigned the grim task of identifying human remains in the burned rubble.
President Donald Trump plans to travel to California on Saturday to visit victims of the wildfires burning at both ends of the state.
In Southern California, crews continued to gain ground against a blaze of more than 153 square miles that destroyed more than 500 structures in Malibu and communities. At least three deaths were reported.