According to the police, you constantly put a puzzle after a blast, look at past events and do analyzes.
– We are looking at who lives at the different addresses to see what the root cause of the explosions is, says Max Åkerwall, Deputy Police Area Manager Stockholm Syd.
Order in several different joints
He says the increase in blasts is due to several people abroad making orders. The order is then passed on at several different stages, to the person who will carry out the crime.
– It is usually a young person, a boy or girl, who is a performer.
Hear more in the video above.