Police received a report of loud bangs at 1:30 p.m. on Wednesday.
An injured man was found in a stairwell at the scene. He has been taken to hospital.
He is said to be awake and able to talk. Otherwise, there is no further information, says Fredrik Svedemyr, police press spokesman.
Two people were arrested shortly afterwards. The suspicions are of attempted murder and aggravated weapons offenses.
It concerns a man in his mid-30s and a man in his 20s, says Svedemyr.
Police on site have cordoned off an area and are knocking on doors for any witnesses.
