The girl was found dead with multiple stab wounds in the residential area of Rosenlund in Södertälje, south of Stockholm, at around 11pm on Friday night.
“The suspect was arrested near the crime scene following a tip off from a witness,” said Claes Eklund at Södertälje police.
Police have combed the area around where the girl was found and have confirmed that they have found the suspected murder weapon.
The girl lived in another part of Södertälje and was visiting the Rosenlund residential area. She was outside when she was attacked and stabbed repeatedly, according to police spokesperson Kjell Lindgren. The girl was later declared deceased in hospital.
Police have not yet established a motive behind the murder.
“As far as we know there is no known relation between the girl and and the suspect,” said Lindgren to news agency TT.
Police have not held any thorough interrogation of the 39-year-old suspect arrested in the vicinity.
“But we have spoken to him,” confirmed Lindgren.
Police confirmed that witnesses to the murder assisted with information both leading to the man’s arrest and in developing a picture of the circumstances and events around the stabbing.
“There are people who have related what happened. They also helped to make it possible for us to arrest him and have submitted detailed descriptions of him.”
Lindgren was unwilling to discuss why the girl was in the area but confirmed that the police believe that they know her purpose there and that she was on her way from Rosenlund when she was stabbed.
The 39-year-old will be subjected to further interrogation when the district court has had time to appoint a duty solicitor to represent him. The police intend to interview further witnesses on Saturday.
Lindgren was unable to confirm when the suspect would be interrogated.
“That we don’t know, there is no scheduled time.”