Fire crews deployed a turntable ladder and some wore breathing apparatus as they inspected a suspected electrical fire in Wisbech.
The fire service was called on Sunday after being alerted to the incident above the Norwich and Peterborough Building Society.
Two crews from Wisbech and a crew from Stanground were called to the building fire in Market Place, Wisbech.
A fire service spokesman said: “Smoke was issuing from two commercial buildings and from the roof of the roof of the four-storey building.
“Fire fighters forced entry through the ground floor wearing breathing apparatus and searched every floor. Ladders and specialist equipment was also used on the outside of the property.”
The spokesman said that a fire was discovered in the wooden fascia between the two buildings, resulting in smoke seeping through into both properties.
“The fire service used positive pressure ventilation to clear smoke from the buildings.
Crews returned to their stations by 4.40pm,” he said.
The cause of the fire was accidental, by electrical.
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