No one has been injured, but windows have been shattered. The police have been on site with multiple units, including a dog patrol.
We have cordoned off the area and the national bomb squad will secure the site before the technicians can begin their work, says police spokesperson Per Fahlström.
Early on Monday morning, the police announce that a man has been arrested and detained in the case, which is classified as reckless endangerment and a violation of the law on flammable and explosive goods.
The police do not want to comment on any potential motives behind the explosion, citing that the investigation is still in its early stages.
In parallel with the large police operation on site, we are also working on intelligence gathering, which includes looking at what kind of motive picture there may be, says Per Fahlström.
The alarm came in just after 11 pm.