Public prosecutor Karin Sandén is leading the preliminary investigation and does not want to comment on how she views the evidence situation and whether all those who are deprived of their liberty in the case will be requested to be detained.

"We are in a critical investigation phase," she told SVT.

A description of the situation confirmed by the police's investigator-in-charge.

"Yes, that's right. This is a very serious crime. We are taking a great many important investigative measures that must not be destroyed by information coming out," says Inspector Jan Staaf.

"A troubled time in Norrköping"

The level of conflict among the criminal groups in Norrköping can currently be described as high.

"We are having a troubled time in Norrköping at the moment. Of course, we wrestle with the national conflict as all major cities do. At the same time, we have internal conflicts between different rival gangs in Norrköping.

Watch and hear more in the video above.