Residents close to the fire at Chandlers Building Supplies have been warned to keep their windows closed as work continues to on the site.
East Sussex Fire and Rescue Service said it will remain at the scene of a serious fire at Portslade throughout today (March 16).
A fire service spokesperson said: “A fire broke out at Chandler Building Supplies, Basin Road, North Portslade at 8.44am on March 15.
“The building has been badly damaged and is due to be dismantled.
“As of 9am, two fire engines remain on scene. This number may increase if needed.
“There may also be further smoke coming from the site.
“Locals are being advised to avoid the area and keep doors and windows closed.
“Some road closures in the immediate area remain in place.
“The fire and rescue service is working alongside Building Control, the Environment Agency, the site owners and demolition crews.
“A further update will be provided around lunchtime.”