German authorities say a 17-year-old Afghan who entered the country last year as an unaccompanied minor has been taken into custody on suspicion he raped and killed a 19-year-old university student.

Dieter Inhofer, prosecutor in the southwestern city of Freiburg, said Saturday that the teen asylum-seeker was identified as a suspect based on traffic video from near the crime scene.

Inhofer tells the dpa news agency that DNA evidence has tied the boy to the crime scene. He was living in the area with a family.

The student vanished on her way home from a party early on Oct. 16. Her body was found in a river later that day.

The suspect hasn't made a statement.

Authorities are trying to determine if he and the young woman knew each other.