I cannot go into details about the person right now, but the person was arrested near the crime scene, says Per Fahlström, press spokesperson at the Stockholm police.
The alarm came in just before 3:30 am on Friday morning after several residents heard a loud bang.
When we arrived at the scene, it turned out that an explosion had occurred at the entrance to the building and caused damage to, among other things, the entrance door, including shrapnel damage, says Per Fahlström.
The area was cordoned off and the national bomb squad has been called to the scene.
They have to secure the area before our forensic technicians go in, says Per Fahlström.
There is no information that anyone was physically injured, and the police have launched a preliminary investigation into gross reckless endangerment.
