The Poundstretcher store in Blackwood is being demolished following a blaze in the early hours of Wednesday morning.
South Wales Fire and Rescue Service say the cause of the fire was bins being set alight.
Fire crews were called out at around 2 o'clock this morning.
Officers say refuse bins were on fire and this had spread to the store room at the back of the shop.
Due to safety concerns the High Street was closed and the electricity supply to a number of shops was cut. Structural engineers were called out to assess the safety of the building.
More top news
A wet and blustery start to the day, but it will brighten up this afternoon!
Well I can promise it's not the nicest of nights out there! Turning wet with heavy downpours in places.
Alfie was diagnosed with retinoblastoma when he was only four months old. Now he and his brother have been recognised for their bravery.