Stockholm - A powerful explosion blew out the entrance to a police station in the southern Swedish city of Helsingborg on Wednesday, an attack authorities linked to their fight against organised crime.
The explosion occurred just after midnight in the city centre, which is home to around 100 000 people.
Prime Minister Stefan Lofven called it "an attack against our democracy" and urged authorities to "step up the fight against serious crime".
The blast, heard from as far away as 20km, caused no injuries but serious material damage. The police station entrance was completely destroyed and dozens of windows smashed.
Police sources quoted by daily Aftonbladet said several kilogrammes f explosives were used.
The head of the local police, Patric Heimbrand, told reporters that investigators were working on the presumption that "criminal circles" were behind the attack. He said police work against gangs was paying off and likely causing "irritation".
Explosives are often used by organised crime rings in Sweden, especially in the south where settling of scores and intimidation are frequent among drug traffickers.
Police and judges are also regularly targeted.