By Walter Gibbs and Anna Ringstrom
OSLO (Reuters) - A suspected far-right gunman in police uniform killed at least 84 people in a ferocious attack on a youth summer camp of Norway's ruling Labor party, hours after a bomb killed seven in Oslo.
Witnesses said the gunman, identified by police as a 32-year-old Norwegian, moved across the small, wooded island of Utoeya in a lake northwest of Oslo Friday, firing at young people who scattered in panic or tried to swim to safety.
Police detained the tall, blond suspect, named by local media as Anders Behring Breivik, and charged him for the killing spree and the bombing of government buildings in Oslo.
Prime Minister Jens Stoltenberg, capturing the shock this normally quiet nation of 4.8 million is experiencing, said: "A paradise island has been transformed into a hell."
Deputy Police Chief Roger Andresen would not speculate on the motives for what was believed to be the deadliest attack by a lone gunman anywhere in modern times.
"He describes himself as a Christian, leaning toward right-wing Christianity, on his Facebook page," Andresen said.
Initial speculation after the Oslo blast had focused on Islamist militant groups, but it appears that only Breivik -- and perhaps unidentified associates -- was involved.
Home-grown right-wing militancy has generated occasional attacks elsewhere, notably in the United States, where Timothy McVeigh killed 168 people with a truck bomb at a federal building in Oklahoma City in 1995.
U.S. Secretary of State Hillary Clinton, among many world leaders, condemned the Norway attacks. "This tragedy strikes right at the heart of the soul of a peaceful people," she said.
Andresen, the deputy police chief, said the casualty toll could still rise. "As of now we have 84 dead at Utoeya," he said. "In Oslo, with the explosion and the impact it had, we are not yet sure if that number is final. At Utoeya, the water is still being searched for more victims."
Teenagers at the lakeside camp fled screaming in panic, many leaping into the water to save themselves, when the assailant began spraying them with gunfire, witnesses said.
"I just saw people jumping into the water, about 50 people swimming toward the shore. People were crying, shaking, they were terrified," said Anita Lien, 42, who lives by Tyrifjord lake, a few hundred meters (yards) from Utoeya.
"They were so young, between 14 and 19 years old."
Survivor Jorgen Benone said: "It was total chaos...I think several lost their lives as they tried to get over to the mainland.
"I saw people being shot. I tried to sit as quietly as possible. I was hiding behind some stones. I saw him once, just 20, 30 metres away from me. I thought 'I'm terrified for my life', I thought of all the people I love.
"I saw some boats but I wasn't sure if I could trust them. I didn't know who I could trust any more."
"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," one survivor, a 16-year-old called Hana, told Norway's Aftenposten.
"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 toward the beach and began to swim."
Hana said the gunman fired at people in the water.
Many sought shelter in buildings as shots echoed across the island that was hosting the annual camp for the youth wing of the Labor Party, the dominant force in politics since World War Two. Others fled into the woods or tried to swim to safety.
Stoltenberg said he knew many of the victims personally. "I know the young people and I know their parents," he said.
"And what hurts more is that this place where I have been every summer since 1979, and where I have experienced joy, commitment and security, has been hit by brutal violence -- a youth paradise has been transformed into a hell."
"What happened at Utoeya is a national tragedy," he said. "Not since World War Two has our country seen a greater crime."
EXPLOSIVES FOUND ON ISLAND
The bomb, which shook Oslo's center in mid-afternoon, blew out the windows of the prime minister's building and damaged the finance and oil ministry buildings.
Police found undetonated explosives on Utoeya, a pine-clad island about 500 metres long.
Breivik's Facebook page appeared to have been blocked by late Friday. Earlier, it had listed interests including bodybuilding, conservative politics and freemasonry.
Norwegian media said he had set up a Twitter account a few days ago and posted a single message on July 17 saying: "One person with a belief is equal to the force of 100,000 who have only interests."
About 10 policemen were outside the address registered to his name in a four-storey red brick building in west Oslo.
The Norwegian daily Verdens Gang quoted a friend as saying he became a right-wing extremist in his late 20s. It said he expressed strong nationalistic views in online debates and had been a strong opponent of multi-cultural ism.
Oslo was quiet but tense after Friday's bombing in the government district littered streets with shattered masonry, glass and twisted steel. Police sealed off the area.
The district attacked is the heart of power in Norway. But security is not tight in a country unused to such violence and better known for awarding the Nobel Peace Prize and mediating in conflicts, including the Middle East and Sri Lanka.
A Utoeya survivor said she was still in shock. "I cannot squeeze out one tear. I cannot believe it," wrote 23-year-old student Khamshajiny Gunaratnam on her blog.
She said participants in the summer camp were just digesting news of the Oslo bombing when they heard shooting.
"'Who the hell is that joker?' we thought. Who would have thought that it actually wasn't a joke?"
Terrified, Gunaratnam hid in toilets in the main building and then fled to the shore. "We fell and stumbled through a lot of bushes and large rocks. I got many scratches."
When the shooting came closer, she jumped into the cold water and was eventually picked up by a rescue boat.
"Even when we had reached the boat, I could not relax...He could still hit us with his machinegun!" Gunaratnam wrote. I did not feel safe. Not at all."
(Additional reporting by Gwladys Fouche, Victoria Klesty, Henrik Stoelen and Ole Petter Skonnord in Oslo, William Maclean in London and Patrick Lannin in Stockholm; Writing by Alistair Lyon; editing by David Stamp)