Helén Nilsson was abducted on the night of March 20, 1989, and her body was found six days later. Jannica Ekblad was a prostitute in Malmö. She was found dead on 4 August 1989.

"Traces of a Serial Killer" - Helén Nilsson was abducted on the night of March 20, 1989, and her body was found six days later. Jannica Ekblad was a prostitute in Malmö. She was found dead on 4 August 1989. Helén had been alive for several days after the abduction and had been raped and abused. A number of leads were followed over the years but the later convicted killer, Ulf Olsson, was not a person of interest to the police until 2002. Jannica was seen leaving together with a man and was never seen again. In 2004, large amounts of Ekblad's blood were found in the summer cabin that belonged to Ulf Olsson at the time of the murder. The investigation is the second-largest in Swedish history, only surpassed by the investigation of the 1986 assassination of Swedish prime minister Olof Palme.—Ulf Kjell Gür