At least 85 people have died after a gunman fired on a Norwegian Labour party youth camp. The attack happened hours after a bomb killed seven in the government district in the capital Oslo.

A wounded woman is brought ashore opposite Utoya island in Norway after being rescued from a gunman who went on a killing rampage (Getty)

Witnesses say the gunman moved across the small, wooded Utoya holiday island firing at random as young people scattered in fear, some hiding behind rocks while others swam for their lives.

Police later identified the attacker as a 32-year-old Norwegian who they linked with the bombing in Oslo earlier on Friday, which left seven dead.

Norwegian media have named suspect Anders Behring Breivik. He has been charged over both attacks.

A 16-year-old, Hana, who survived the shootings, told Norway's Aftenposten: "We had all gathered in the main house to talk about what had happened in Oslo. Suddenly we heard shots. First we thought it was nonsense. Then everyone started running,"

"I saw a policeman stand there with earplugs. He said 'I'd like to gather everyone'. Then he ran in and started shooting at people. We ran down towards the beach and began to swim."

Hana said the gunman fired at people in the water. Another newspaper reported that a man dressed as a policeman was seen shooting "wildly".

In a blog that has been translated into English, one survivor is quoted describing how she swam for her life as the gunman fired into the water.

Twenty-three-year-old Khamshajiny Gunaratnam is a youth politician in the Norwegian Labour Party.

She said: "I swam. Then some boats came to save us. One boat threw us lifejackets and then had to drive on. The next boat came and grabbed us. Even when we had made it into the boat, I couldn't relax.

"There wasn't a 'yes, we're saved!' feeling. He [the gunman] could still hit us..."

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Prime Minister Jens Stoltenberg had been due to visit the summer camp, where nearly 600 young people aged 15-30 had gathered for the Labour party youth event.

He said "a youth paradise had been turned into hell".

Read more: Norway attacks are national tragedy

British Prime Minister David Cameron has sent his sympathies to the Norwegian people: "The Norwegians are old friends and allies and neighbours of Britain, and I know that everyone in Britain will want to stand with the Norwegian people in the days of sorrow that lie ahead.

"Also, we will want to make sure that we learn, like others, any lessons there are to learn about how to be more secure against horrific outrages like this, and that's something we can discuss at the National Security Council on Monday."

The Queen has written to the King of Norway to express her shock and sadness at the attacks.

She said her and the Duke of Edinburgh's thoughts were with the Norwegian people.

Her message to King Harald read: "I am deeply saddened and shocked by the tragic loss of life of so many people on the island of Utoya and in Oslo."

Norway attacks -  Twitter reaction
@dltq:
This is the most dramatic day in Norway since WWII
@ketilbstensrud: SMS from Utøya eye-witness: "I'm safe. We've hidden in a tree. One of us is shot twice in the foot."
@BradFrenette: Utoya gunman captured: "190cm, blonde, light skin, athletic, in police uniform" via TV2.
@WilliamJHague: Horrific attacks in Oslo - we condemn all acts of terrorism and will stand shoulder to shoulder with Norway in the face of such atrocities.
@SarahBrownUK: so saddened by young Norwegians attacked brutally as they were meeting to look at how best to engage with politics and public service