A bomb has hit a government building in Norway's capital Oslo killing at least two people, according to local reports.
However it is not clear who or what is behind the explosion, but people have been speculating on which groups might want to target the country.
Norway is a Nato member and involved in Afghanistan, however it has been scaling down its involvement in operations in Libya.
Yesterday Norwegian Foreign Minister Jonas Gahr Store reportedly said the time was ripe to open negotiations with banned Islamist terror group Al-Shabaab.
Al Qaeda have also been known to be active in Norway, with three arrests related to a planned terrorist attack in the country last year.
Nearby Sweden was attacked in December 2010.
The only concrete supposition that would emerge in a Norwegian context would be al Qaeda. There has been specific mention of Norway [in their communications], alongside a number of other countries that have been part of the war on terror [and] part of the war in Afghanistan, including on one occasion fairly recently after the killing of Osama bin Laden. That is the only concrete angle there is to it -- but the police have not yet indicated anything in terms of where they are looking, as far as I understand it. There's still quite a bit of work to be done before they have an overview of what happened, or even an overview of the extent of the damages and the number of people killed and injured.
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