The two suspected teenagers, aged between 15 and 18, are also being held in custody on aggravated weapons offenses that allegedly occurred on the same occasion, according to the Prosecution Authority.
Detention hearings will be held on Monday afternoon, starting at 3 p.m.
According to P4 Östergötland, another person is suspected of involvement in the murder in Norrköping, where a man in his 20s was shot and later died of his injuries.
The two teenagers who have now been requested for detention are also suspected of a murder in the Oslo area last weekend. In the murder in Norway, a man in his 20s was killed; according to Norwegian police, he was linked to criminal circles.
