-There were two people in the store, one of them was taken to hospital with knife injuries to his back and one hand, says police spokesman Stefan Gustafsson.
Two masked perpetrators left the scene on foot.
The police state that the perpetrators did not receive any loot from the robbery in that case.
It is now being investigated whether the three crimes have any connection to each other.
-We can not rule out that it is connected, there are similarities in the description of the perpetrators, says Stefan Gustafsson.
The police state that they have secured certain tracks, and have, among other things, searched for the robbers with a dog.
-We have three places to monitor in the same part of the region, so the situation is quite strained. We record witness statements and secure all evidence we can.