There have however as yet been no reports of any injuries or property damage in connection with the fires, the exact cause of which has not yet been established.
Meteorological agency SMHI has also warned of an increased risk of forest fires in southern and central Sweden, with the weather expected to stay extremely dry this week.
A series of fires in northern parts of Hälsingland remained out of control early on Monday morning.
“It has been windy all night, which makes it hard to put out the fires,” rescue worker Peter Schönberg told the TT news agency. Schönberg is leading the operation to fight the fires raging across 500-1,000 hectares north west of Hassela.
Kerstin Danckwardt lives in Ässjö, around two kilometres from the nearest fire.
“We can see how they are water-bombing the fire with a number of helicopters. Of course it’s terrible with a fire this big in the forest but we personally are not that worried yet,” she said.
A few kilometres further south, in Furuberg, Nils Tingerlöf, has already packed his car in case he needs to leave the area at short notice.
“It was raining burned leaves and pine needles on the cars and it felt like sitting in a big bag full of smoke. It was quite scary. But today the wind has changed and there’s less smoke,” he said.
A total of around 180 rescue workers and military personnel are working to extinguish the fires.