OSLO — Powerful explosions shook central Oslo on Friday afternoon, blowing out the windows of several government buildings, including one housing the office of the Norwegian prime minister. The state television broadcaster, citing the police, said 7 people were killed and at least 15 injured; a spokeswoman for the prime minister, Jens Stoltenberg, said he was “safe and not hurt.”
Shortly after the explosions, which appeared to be a bomb attack, a man dressed as a police officer opened fire on a summer camp for young members of the governing Labor Party on the island of Utoya about 25 miles northwest of the city, and wounded at least five, a Norwegian security official said.
“The situation’s gone from bad to worse,” said Runar Kvernen, spokesman for the National Police Directorate under the Ministry of Justice and Police, adding that most of the children at the camp were 15 and 16 years old.
A terror group, Ansar al-Jihad al-Alami, or the Helpers of the Global Jihad, issued a statement claiming responsibility for the attack, according to Will McCants, a terrorism analyst at C.N.A., a research institute that studies terrorism. The message said the attack was a response to Norwegian forces’ presence in Afghanistan and to unspecified insults to the Prophet Muhammad. “We have warned since the Stockholm raid of more operations,” the group said, according to Mr. McCants’ translation, apparently referring to a bombing in Sweden in December 2010. “What you see is only the beginning, and there is more to come.” The claim could not be confirmed. It is not uncommon for terrorist groups to advance claims of responsibility for high-profile attacks, only to have the claims prove to be spurious.