Eight reported injured in blast which has damaged buildings including office of Norwegian prime minster.
Several people have been injured in a large explosion which has damaged government buildings in central Oslo, including the office of the Norwegian prime minster.
A Reuters correspondent said he counted at least eight injured people after the unexplained blast.A photo posted online showed people looking on as smoke rose drifted through the streets. The caption for the picture said "an entire block exploded".
The tangled wreckage of a car was outside one building but the cause of the blast was unknown with police and fire officials refusing to comment.
The explosion at around 3.30pm (2.30pm BST) blew out most windows on the 17-storey building housing prime minister Jens Stoltenberg's office, as well as nearby ministries including the oil ministry, which was on fire. Video showed the pavement littered with shattered glass. Norwegian news agency NTB said the prime minister is safe. Newspaper offices in the area were also reportedly damaged.
The city centre - which usually empties in July as Norwegians take holidays - is currently closed off with all public transport to and from the centre suspended.
