"A lot of vehicles have slid off the road," said Tomas Schäufele, commanding officer on duty at Norrbotten police's county communications centre.
"Right now there is a truck overturned on the E10 west of Morjärv. Nobody has been hurt but there is petrol leaking from the tank and emergency services are on their way there," he said.
Police in Jämtland have also received reports of treacherous road conditions as motorists struggle to keep control of their vehicles.
Residents of Östersund, 550 kilometres north of Stockholm, awoke to ten centimetres of snow on the ground on Wednesday morning. Storuman, a further 200 kilometres north, saw 20 centimetres of snow fall overnight.