A gunman dressed as a police officer has attacked a rally at a youth camp that Norwegian Prime Minister Jens Stoltenberg was due to attend, outside the capital Oslo. Four people have been reported dead.
News of the shooting came after two people were confirmed dead following at least one blast in Oslo, which exploded outside government buildings.
Utøya is home to a summer camp run by the workers youth league, which is part of the ruling Labour Party
Stoltenberg was due to attend a rally at the summer camp - around 20 miles from the capital - tomorrow, according to reports.
Police are sending anti-terror chiefs to the youth camp and are evacuating the Island, AP reports.
The BBC reported that one person had been arrested at the youth camp, and is being questioned at a local police station.
An eyewitness has told Norway's state broadcaster there are up to 20 dead.