The man, a Polish citizen, currently based in Gothenburg but living in Linköping at the time of the murder, denied the charges. He initially refused to provide a blood sample for DNA testing, fuelling press speculation that he was involved.
However, he was eventually forced to provide a blood sample after police were granted a court order late on Monday.
The man’s lawyer, Leif Silbersky, claims his client may seek damages after the events of the last two days.
“He’s not feeling particularly great,” Silbersky told Aftonbladet. “But what would you expect after being suspected of two murders?”
Silbersky also accused the police of allegedly interviewing the man without his lawyer present.
After the media’s initial jubilation that a suspect had finally been arrested, four months after the brutal killings of Mohammed Ammouri and Anna-Lena Svenson, the latest development will come as a bitter blow to the families of both victims.
The release of the unnamed man will also heap further pressure on Tommy Håkansson, the police inspector leading the investigation, and his team who have struggled to solve this apparently motiveless crime.
They have accumulated over 12,000 documents relating to the case and held 2,000 interviews but are still lacking a serious suspect.
Mohammad Ammouri was on his way to school when he was stabbed while Anna-Lena Svenson was only 25 metres from her apartment block and on her way to her job in central Linköping. The boy died at the scene and Mrs Svenson died from her wounds in hospital some hours later.
The murderer escaped but police found his blood-stained clothes hidden near the scene of the murder and concluded that the killer had seriously injured his own right hand in the attacks. DNA samples were taken from the clothes as well as from the so-called butterfly knife which was found shortly after the murders.