Eyewitnesses have been giving their accounts of the chaos following the bomb explosion near government buildings in the Norwegian capital Oslo.
Ingunn Andersen, a journalist with Norwegian public radio NRK, described the scene shortly after the blast: "Some people covered with blood are lying in the street.
"There is glass everywhere. It is total chaos. The windows of the all the surrounding buildings have been blown out."
"The political centre of Oslo just exploded," wrote one Twitter user in the city, finansakrobat, who said he had narrowly missed being at the scene of the blast.
"I should have been standing in front of the blast. Just chance that I was late. I should be dead."
'Fearing the worst'
Siv Hartvigsen, who was visiting the city on holiday, said she had fled from the danger as soon as she could.
"We were shopping at Eger Torget which is just above the Stortinget [Norway's parliament], and we just heard a big bang," she told the BBC.
"The whole building was shaking big time. We could see the hairdressers on the second floor of the building next door.
"Its windows were blown out as we watched it and then the fire alarm went and we had to run outside.
"There were people running all over the place and the only safe thing I could think of was to run away as far as possible."
Eric Wikstrom told the BBC he had been working near the scene of the blast.
"I saw some people injured outside - I took a photo of a shoe that had blood on it, and wondered what had happened to its owner," he said.
"I feel shaky - it's surreal. Norwegians have never experienced anything like this before. We've heard it happen in the US and in Britain, but not here. I feel sick.
"People have been trying to phone friends and family to find out if they are OK. But the phones have been down, so I'm still not sure if everyone I know is OK."
Ole Tommy Pedersen, who was standing at a bus stop about 100m (yds) from the blast scene, said he had seen almost all the windows in a 20-storey government building shatter, with smoke billowing from the bottom floors.
"I saw three or four injured people being carried out of the building a few minutes later," he told the Associated Press news agency.
Hearing a blast "like thunder" from about a mile away, British resident Ben McPherson immediately assumed it was a terrorist attack.