The fire in Sigtuna was judged to be too dangerous for firefighters to enter the property.
“The entire roof has collapsed. The house will burn down to the ground and we will keep one position in place during the night,” Johan Winsnes from the Stockholm emergency services told news agency TT.
At one point on Wednesday evening between 40 and 50 firefighters battled the blaze. By around 2.30am however only one crew remained and work had started to wind down, focusing solely on making sure the fire did not spread.
It is thought that the building – a restaurant belonging to a conference centre – was empty and no injuries have been reported.
“We will be able to investigate that once the fire is completely extinguished and cooled down,” Winsnes noted.
Police have launched a preliminary investigation into carelessness endangering the public.