Who shot the 21-year-old man in an apartment in Västra Blombacka in Södertälje is not clear.
However, three teenagers are convicted of aiding and abetting the murder.
The Södertälje District Court sentences two now 19-year-old men to 13 years and ten months in prison each, while a 17-year-old boy is sentenced to two years of closed youth care.
The background to the murder is believed to be an ongoing gang conflict.
"The circumstances of the crime are therefore particularly aggravating," says Judge Caroline Hellström in a press release.
During the trial, evidence was also presented against two minors. One of them, who was 13 years old at the time, is deemed to have made himself guilty of aiding and abetting the murder by stealing keys to the residence and handing them over.
