At least seven people are killed in bombing and 30 are feared shot at a political youth camp near capital Norway has suffered the worst attack in its postwar history as terrorists bombed Oslo’s central government district and opened fire at a political youth camp on an island near the capital. At least seven people were reported killed and scores injured in the city centre, while unconfirmed reports on Norwegian television said up to 30 young people may have been shot on the island by a man dressed as a policeman. The Oslo blast damaged buildings and blew out windows over more than a half-mile radius, filling the area with smoke and littering it with shards of metal. Emergency services were still trying to assess the scale of the attack, combing offices in the area in the search for more victims. The detonation took place near the 17-storey government building where the prime minister has his offices and the headquarters of Norway’s biggest tabloid paper, VG. Witnesses said tables in the paper’s basement cafeteria were smeared with blood and scattered with glass and other debris. Residents were told to stay away from the town centre, or stay in their homes and hotel rooms. In what Norwegian police said was a co-ordinated attack, about 700 youth members of the Labour party, some as young as 15, who were holding their annual summer camp on an island of Utoya, a lake west of Oslo, came under fire by a man dressed as a policeman armed with an automatic weapon. According to tweets by people at the event, some children escaped by climbing trees, hiding in the bushes or swimming away from the island. One party youth member tweeted: “We are sitting down by the beach. A man is shooting clothed in a police uniform. Help us! When are the police coming to help us!” Counter-terrorist police flew to the island and it was reported that a man, described in reports as tall and blond, had been arrested. The prime minister, Jens Stoltenberg, who was due to attend the camp today, was reported to have been working at home and to have been unharmed by the blast, as were the rest of the cabinet. Stoltenberg appealed to Norwegians not to be cowed. “Co-workers have lost their lives today. It’s frightening,” he told the broadcaster NRK. “That’s not how we want things in our country. “But it’s important that we don’t let ourselves be scared. Because the purpose of that kind of violence is to create fear.” Those close to the site described the blast’s force as devastating. “The whole building was shaking. It was dancing,” said Jon Magnus, VG’s chief foreign correspondent, who was blown out of his chair by the force of the explosion. “There was glass flying through the newsroom. I was on the far side of the building from where the prime minister’s office is. The entire glass front of our building has been blown out.” It was unclear who was behind the attacks, but there has been growing unease in Norway that the country had little protection against such assaults, while exposing itself to terrorism through its military operations abroad. There was speculation that yesterday’s attacks could be linked to Norway’s military involvement in Nato operations in Afghanistan, where it has 500 soldiers, or Libya, where Norwegian jet fighters are flying sorties. Norwegian television reported that a previously unknown group called “Helpers of the Global Jihad” had posted a message online claiming the attacks were “only the beginning” of a response to the decision by Norwegian periodicals, like other Scandinavian media, to publish cartoons portraying the prophet Muhammad. Last week a Norwegian prosecutor charged an Iraqi Kurdish cleric, Mullah Krekar, the founder of the Ansar al-Islam militant group, with making death threats against Norwegian politicians. In July last year police arrested three Muslim immigrants from Iraq, Uzbekistan and China for allegedly plotting bomb attacks using peroxide explosives. The authorities said the suspects had links with al-Qaida and one of them visited the Pakistani tribal area of Waziristan, an al-Qaida stronghold. Norway presented a softer target than other western capitals with experience of terrorism. Government buildings were not protected by bollards or anti-blast curtains. Observers predicted Norway’s relaxed attitude to security would change, as in neighbouring Sweden, which was hit by a suicide blast against Christmas shoppers in Stockholm. The bomber, Taimur Abdulwahab al-Abdaly, was an Iraqi-born Swede who studied in Britain. Norway Europe Global terrorism Julian Borger Peter Beaumont guardian.co.uk