It's about a 15-year-old boy who was arrested in the Stockholm area on Saturday, says the Prosecutor's Office spokesperson.
The boy is suspected of murder, attempted murder, and serious weapons offenses. He was detained in absentia when he was arrested by the police.
The last time to request his detention is on Christmas Eve at 12 o'clock.
A 16-year-old girl and a 28-year-old man have already been detained, suspected of involvement in the murder.
The girl, who denies the crime, was detained on probable grounds suspected of murder, attempted murder, and serious weapons offenses, reports local media.
The 28-year-old man, who also denies the crime allegations, was detained on probable grounds suspected of aiding and abetting murder and attempted murder. He is also suspected of serious drug offenses.
It was at 19:00 on Monday when a 30-year-old woman was injured in a shooting in a multi-family house in the Teleborg district. She was taken to the hospital, but her life could not be saved.
A 30-year-old man was also lightly injured.