Blast Rocks Central Oslo, Norway PM's Office

The cause of the blast was unknown but the tangled wreckage of a car was outside one building and the damage appeared consistent to witnesses with that from car bombs. Police and fire officials declined comment on the cause.

The blast blew out most windows on the 17-storey building housing Stoltenberg’s office, as well as nearby ministries including the oil ministry, which was on fire.

Heavy debris littered the streets and a tall plume of brown smoke over the city centre.

A Reuters correspondent counted at least eight injured people. Norwegian news agency NTB said that Stoltenberg was safe in the blast, which happened around 3:30 p.m. (2:30 p.m. British time).

“It exploded — it must have been a bomb. people ran in panic and ran. I counted at least 10 injured people,” said Kjersti Vedun, who was leaving the area.

NATO member Norway has sometimes in the past been threatened by leaders of al Qaeda for its involvement in Afghanistan. It has also taken part the NATO bombing of Libya, where Muammar Gaddafi has threatened to strike back in Europe.

However, political violence is virtually unknown in the country.  

Nearby ministries were also hit, including the oil ministry, which was on fire. Heavy debris littered the streets.

John Drake, senior risk consultant, at London-based consultancy AKE said: “It may not be too dissimilar to the terrorist attack in Stockholm in December which saw a car bomb and secondary explosion shortly after in the downtown area.

“That attack was later claimed as reprisal for Sweden’s contribution to the efforts in Afghanistan.”

The Reuters correspondent said the streets had been fairly quiet in mid-afternoon on a Friday in high summer, when many Oslo residents take vacation or leave for weekend breaks.

The tangled wreckage of a car was outside one building, as well as the damage to the buildings, appeared consistent to witnesses with that from car bombs.

THREATS

NATO member Norway has sometimes in the past been threatened by leaders of al Qaeda for its involvement in Afghanistan. But political violence is virtually unknown in a country known for sponsoring the Nobel Peace Prize and mediating in international conflicts, including in the Middle East and Sri Lanka.

It has also taken part the NATO bombing of Libya, where Muammar Gaddafi has threatened to strike back in Europe.

David Lea, Western Europe analyst, at Control Risks said: “There certainly aren’t any domestic Norwegian terrorist groups although there have been some al Qaeda-linked arrests from time to time. They are in Afghanistan and were involved in Libya, but it’s far too soon to draw any conclusions.” Reuters