Swedish police arrest four on suspicion of plotting terrorist attack

The four were arrested in Gothenburg suspected of plotting terrorism, security police spokesman Stefan Johansson has confirmed.

It is however not yet clear whether the arrests are linked to the 10-year anniversary of the September 11 terrorist attacks in the US.

Police in Gothenburg have been reported as saying that they had evacuated an arts centre in the city overnight on Sunday due to a threat deemed to pose "serious danger for life, health or substantial damage of property".

They said they had assisted security police with the arrest and declined to give any further comments.

Mia Christersdotter Norman, the head of the Roda Sten arts centre in Gothenburg is also reported as saying that about 400 people were celebrating the opening of an international biennial for contemporary art at the time of the evacuation.

"Around midnight I was called out by the police and they said there was a threat to the building and asked us to quietly stop the party, which we did and everyone left," Christersdotter Norman was reported as saying by Associated Press.

"Police have searched the building but they didn't find anything," she said, adding the arts center would re-open as usual on Sunday.

In October last year, Sweden raised its terror threat alert level from low to elevated.

Just a few months later in December, suicide bomber Taimour Abdulwahab blew himself up in downtown Stockholm among panicked Christmas shoppers, injuring two people, causing shock in a country that had largely been insulated from terrorism.

Scandinavia has largely been focused on Islamic terrorism since the September 11 attacks, but in the wake of the killing spree in Norway in July by Anders Behring Breivik – a rightwing, anti-immigrant Norwegian – the European police agency said it was setting up a taskforce to help investigate non-Islamist threats in Scandinavian countries