The police soon established a connection between the three murder cases, as the crimes apparently had been motivated by robbery. Evidence also suggested that the killer was also behind a recent bank robbery in
Låby outside Halden. After months of painstaking investigation, carried out in cooperation with
National Criminal Investigation Service, the police were able to apprehend Roger Herbert Haglund, a 55-year-old family man from Tistedalen, on 1 May 1993. The evidence against him was strong from the onset. Haglund's alibi did not hold up to scrutiny, and he was in dire financial straits. To the police investigators who interrogated him, Haglund came across as an unusually cold person. Confronted with the evidence the investigators had uncovered, Haglund confessed, then later retracted his confession, claiming that the infamous murderer and sex offender
Edgar Antonsen, who had taken his own life the same year, had forced him to falsely confess to the crimes. When the trial began Haglund folded under the weight of the
prosecutor's case, and he confessed again. Public prosecutor
Lasse Qvigstad presented the accused as a cold and calculating man who murdered his defenceless victims, then took his time to look for valuables in their homes. Roger Herbert Haglund, who the court described as an "ice cold psychopath," was found guilty and on 26 April 1994 sentenced to 21 years in prison and 5 years
preventive detention. The day after the sentencing it was uncovered that Haglund was planning to take a hostage and escape from prison armed with a fake dynamite stick, and he was immediately transferred to a maximum security prison.{{cite news |last= Bakkeli |first= Tom |url= https://web.retriever-info.com/services/archive.html?method=displayDocument&documentId=055016199404295854761&serviceId=2 During the investigation, Haglund was connected to an unusual brutal double murder in Sweden, committed a few years prior, but he was never prosecuted. ==Sentence and release==