Anders Hansson, the 18 year old perpetrator, was discovered January 12, 1979, when he tried to give a 94-year-old woman a juice mixed with detergent. However, the woman spat out the drink and called on the staff. When the staff came Anders Hansson was standing in the corner of the room and repeated several times, without anyone even said anything to him, that he had not done anything. When other members of the staff smelled on the 94-year woman's breath, they noticed a distinct odor of Gevisol. All employees were ordered to remain at the ward. Anders Hansson first blamed a patient for the incident, but admitted soon to the police what he had done.
Anders Hansson alleged motive for his actions was that he wanted to shorten the aged patients' suffering. He admitted during the interrogations 27 murders and 15 attempted murders. Both the police and the forensic chemists believed, however, it was unclear how many of the patients who actually had died of phenol poisoning. When the indictment after four months was finished, the chief prosecutor Sten Runerheim could prove 16 murders and 11 attempted murders. Anders Hansson was finally sentenced at the Malmö District Court to undergo inpatient psychiatric care for 11 cases of murder and 16 cases of attempted murder.