Key Points
- Two people were killed and 14 wounded in a Norway shooting.
- Police say it is being investigated as an act of terrorism.
The Norwegian security service raised the country's terror alert level to the highest level, hours after a gunman opened fire at an LGBTQI nightclub in central Oslo on the eve of the city's Pride parade.
The danger of a terrorist threat was "exceptionally" high, the head of the PST security service said.
Roger Berg said the early Saturday shooting, which claimed two lives and injured at least 21 other people, was considered an Islamist-motivated terrorist attack.
Norway's terrorist alert level is now five. Previously it was three.
Police said a suspect had been arrested following the shootings, which occurred around 1am (local time) in three locations, including a gay bar, in the centre of the Norwegian capital.
The gunman fired in and around the London Pub, a bar and nightclub which bills itself as Oslo's "gay headquarters since 1979." Shots were also fired at other venues nearby, in an area of the city known for its nightlife.
Witnesses said they saw a man with a bag arrive at the scene, take out a gun and start shooting. Panic ensued.
Members of the public helped in the arrest of the suspect and police later thanked them for their efforts.
Of the 21 people injured, police said 10 were in serious condition. One man who died was in his 50s, the other in his 60s.
Police Inspector Tore Soldal said that the attacker was a Norwegian citizen of Iranian origin. They found a pistol and an assault rifle during a search of his flat. Both were unregistered.
The suspect's defence attorney, John Christian Elden, told Norwegian broadcaster NRK it was too early to speak about a possible motivation and that the man's mental health needs to be evaluated.
"The police are investigating the events as a terrorist attack," police said in a statement.
A Pride march that was due to take place in the capital on Saturday afternoon was called off following the violence in the normally tranquil city.
"All events linked to Oslo Pride have been cancelled" following "clear" recommendations by police, the organisers wrote on Facebook.
Large areas of Oslo's party mile were cordoned off on Saturday as police continued their investigations.

Police stand guard at the site of a mass shooting in Oslo, Norway, on Saturday. Credit: Javad M. Parsa/AP
The shootings happened near the London Pub gay club, the Herr Nilsen jazz club and a takeaway food outlet.
Heavily armed police equipped with bulletproof vests and helmets were patrolling the scene of the shootings.
'Bleeding man on the ground'
"He looked very determined about where he was aiming. When I realised it was serious, I ran. There was a bleeding man lying on the ground," a woman who saw the incident told the Verdens Gang newspaper.
Another witness quoted by the paper mentioned the use of an automatic weapon, which the police did not confirm.
"There were a lot of injured people on the ground who had head injuries," he said.
According to an NRK radio journalist present at the time of the shooting, the shooter arrived with a bag from which he pulled out a weapon and started firing.
Eight people were taken to hospital and six others were taken care of by a medical service.
"Some are described as seriously injured, others as more lightly injured," said Mr Barstad.
Generally peaceful Norway was the scene of bloody attacks on 22 July 2011 when right-wing extremist Anders Behring Breivik killed 77 people.
He first detonated a bomb near the government headquarters in Oslo, killing eight people.
He then disguised himself as a policeman and went on a shooting spree at a summer camp for left-wing youth on the island of Utoya, killing another 69 people — most of them teenagers.