The house, in Biskopsgården, is the residence for several convicted criminals, including someone involved in the Vår Krog & Bar double murder and mass shooting at Vårväderstorget a year and a half ago, which was itself seen as a settling of scores in the organized crime world.
Many people were inside the apartment when the explosion happened “it could have ended even worse” says police spokesperson Thomas Fuxborg.
The police call the incident “despicable” and have called in extra resources, with forensic experts investigating the scene and officers knocking doors and trying to find the perpetrator before events escalate further, reports Swedish Radio.
In a plea for information from the public, Fuxbom said: "Please contact us now, before this spirals completely out of control".
Talking to Radio Sweden, police spokesperson Ulla Brehm said that people in the area are devastated by the news.
"This is an area with a lot of families and children. They are of course very concerned about the explosion," she said, adding that there have been shootings and violent disturbance in the area in the past, but this is one step further in the violence when a small child become the victim.