"We've been on site all night. We work broadly, knock on doors, interview witnesses and look at material from surveillance films," says Rebecca Roos, who is in charge of the preliminary investigation.
Could the incident be linked to the increased gun violence that is now taking place in many other places in Sweden?
"I understand that there is concern when something like this happens. We work very broadly and we don't rule anything out.
Working to create a sense of security after the incident
How do you assess the security situation in Borlänge after what has happened?
"It's hard for me to judge. We are working to create a sense of security all the time and we will now have extra staff in the area," says Rebecca Roos.
In the video: Come along to the place where shots were fired – and hear the police chief talk about the work after the shooting.