The fire was in a new part of the hospital that is being built. A huge black column of smoke rose into the sky, reports news agency TT.
"There was insulation, foam, which had caught fire for some reason. It is very flammable and energy-rich material and a fire in it becomes incredibly intense, hence the huge column of smoke," says Lars Wendel, Director of Communications at the emergency services in the Karlstad region,to TT.
After just over an hour, the fire was extinguished. It had not spread to the hospital. The evacuation of the four wards was done as a precaution.