A Swedish prosecutor on Tuesday filed preliminary charges of plotting murder against four men initially suspected of preparing a terrorist attack in the country's second largest city.
The men, aged 23 to 26 and of Somali and Iraqi origin, were arrested in a sting in Goteborg late Saturday that also involved the evacuation of an arts center.
The arrests _ on the eve of the 10th anniversary of the Sept. 11 terrorist attacks in the United States _ spread jitters across Sweden, which saw a suicide bomber blow himself up on a pedestrian street in Stockholm in December.
Police have released little information about the case, and it wasn't immediately clear why prosecutor Agnetha Hilding Qvarnstrom dropped the suspicions of terrorist activity on Tuesday.
Prosecution spokeswoman Karin Rosander said the category of the crime might change at a later stage.
"It is not unusual that when you get new information during the course of an investigation the classification of a crime changes," Rosander said.
She also pointed out that the burden of proof is greater for terror crimes, with stricter requirements on proving intent than for crimes such as murder.
Swedish authorities didn't name the suspects, but court documents show that they live in the Goteborg area. Three men are of Somali origin and one was born in Iraq. One is a Somali citizen and the rest are Swedish nationals.
Lawyer Bjorn Sjolander, who represents one of the suspects, said his client denies committing any crime.
"He doesn't know what the police are talking about at all," Sjolander said.
Lawyers of the other three suspects didn't immediately return calls.
The SAPO security service has said that Goteborg police and a national police anti-terror unit were involved in the arrests Saturday.
Goteborg police said they had evacuated the Roda Sten arts center, located beneath the city's landmark half-mile (930-meter) Alvsborg bridge, because of a threat deemed to pose a "serious danger to life, health or substantial damage of property."
The six-lane bridge runs over Goteborg harbor connecting the mainland to the island of Hisingen. It is a vital link from the Norwegian capital, Oslo, to southern Sweden.