Police say it is 'highly unlikely' they will find any more survivors inside a block of flats which was ravaged by fire in Reading.
Emergency services were called to the building near Grovelands Road at around 2.56am today (December 15).
One person is confirmed to have died as a result of the blaze, while a number of others are unaccounted for.
Superintendent Steve Raffield of Thames Valley Police said: "We've been working alongside our partner agencies to do everything we can to find signs of life.
"But sadly it is highly unlikely we will find any further survivors in the building.
"The building itself is unstable and it will be a complex operation for our teams as we move through today.
"We expect this phase of the operation to continue into the evening and perhaps beyond."
Officers have arrested a 31-year-old man on suspicion of arson and murder, who remains in custody.
Fire crews arrived within eight minutes of receiving reports of the blaze.
Doug Buchanan from Royal Berkshire Fire and Rescue Service said: "Our teams have been working incredibly hard since the early hours of this morning.
"At the height of the fire, there were around 50 firefighters at the scene from stations across Berkshire and Oxfordshire."