Explosion damages apartment building entrance in Västerås

An explosion occurred at the entrance of an apartment building in Västerås, Sweden, late Friday night. The incident caused damage to the building's entrance and broken windows. No injuries have been reported. Police have launched an investigation into a serious offense involving dangerous substances. The national bomb squad is en route to the scene, and authorities have cordoned off the area. The police have not commented on any arrests or whether the address was previously known to them.