The shots were fired inside the facility, but not in the same room where the match was being played, according to police. The hall is located next to a school in the Solberga area.
"I don't know what kind of premises the shooting took place in, but there is a sports hall upstairs and a football match is going on. There are a lot of people there, but they were not in the exact space where the shooting took place," says police spokesman Daniel Wikdahl.
The gunshots were reported at around 9 p.m. The victim was first treated by people at the scene before police and ambulance crews arrived. Police are not releasing any details about the victim.
The perpetrator has fled the scene and the search is ongoing, but no one has been arrested so far, Wikdahl says.
A preliminary investigation into suspected attempted murder has been launched.
Police do not want to say whether the person who was shot was a man or a woman.
The people who were at the sports facility for the football match were evacuated at around 10 p.m.
After the incident, police ordered that trains not stop at the nearby Älvsjö station. The order was lifted at 10:40 p.m.
During the evening, police technicians began investigating the crime scene.
