Sweden's security police raided the administrative office of a mosque in the country's second largest city , the force said on Sunday.
Security police spokeswoman Sirpa Franzen said Thursday's raid against the Bellevue Mosque in Goteborg was prompted by prosecutor Agnetha Hilding Qvarnstrom, who heads the investigation against three men arrested on the eve of the 10th anniversary of the Sept. 11 terrorist attacks in the United States.
Mosque officials weren't immediately available for comments.
Franzen declined to say if the raid was connected to the arrests and wouldn't give more details. The force only confirmed the operation, following a report in a GT tabloid.
The men, of Somali and Iraqi origin, were arrested as around 400 people were evacuated from an arts center and were initially suspected of plotting a terrorist attack. However, the charges were later changed to preparing murder and the prosecutor said it related only to one individual.
The arrests and evacuation of the arts center _ which is located beneath the city's landmark half-mile (930-meter) Alvsborg bridge _ spread jitters across Sweden, which saw a suicide bomber blow himself up on a pedestrian street in Stockholm in December.