Men near Oslo blast describe immediate aftermath

When a routine, quiet Friday in Norway's capital, Oslo, was suddenly shattered by an explosion that rocked a government building and killed at least seven people, Christian Aglen and Lauritz Raustol were nearby.

Neither could imagine that what had just happened -- could happen -- in their normally placid country.

The Oslo blast was one of two attacks in Norway Friday. In the other, some 84 people lost their lives in a shooting spree at a youth camp on a nearby island.

At last one suspect has been arrested for allegedly carrying out both attacks.

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Aglen, who works in the building next to the one that was targeted, told "Early Show on Saturday Morning" co-anchor Rebecca Jarvis he suddenly "felt an intense shock. The entire building was shaking for a few seconds, and immediately, my first thinking is, 'My goodness, this is an earthquake.' But then I realized, you know, we're not prone to earthquakes, in this part of the country, at least. And that shaking subsided and I realized immediately (that) this has been an explosion.

"I looked outside my window -- fortunately, my window stayed intact. But the windows in the nearby buildings were shattered. We had to evacuate the building immediately. We tried to get through the main entrance, but the main entrance is facing the government building, and there was shattered glass everywhere. And it was impossible to walk through there. So we had to go from behind. And then I walked to the front of the building. And I saw one person injured, on the ground. She was being attended to by other people. And I was just taking photos and videos and sharing it on Twitter and Facebook as fast as I could."

Raustol told Jarvis he "wouldn't expect" an act of terrorism in his country "at all. I was really shocked.

"At first, I thought it must be a gas explosion. But then I realized the magnitude, and I saw that glass was shattered, you know, several hundred meters away from the government buildings. And I realized something must have happened, something big.

"But it's -- it's very strange to me, because I've been living in the Middle East for a year now. And seeing that this can happen in my own country, that has been so peaceful and stable for so many years, it's very strange."

Raustol says his mother also works near the blast scene, but he knew she wasn't there at the time.

Still, "When things like this happen, you -- I think your logic kind of sense of behavior disappears. So ... I just left work and I ... was actually scared that the windows had been shattered at my mother's office, so that, you know, her computer and information, like work information, would be destroyed because of the rain that was predicted.

"So I actually went inside the building even though there were -- the fire alarm was still ringing, and I went back into the office to see that everything was OK, and I even called the security company to tell them there's just been an explosion, so there's no reason why they should come. Yeah, it was very strange.

"And then suddenly, I realized that the fire alarm was going on and I had to leave, and that I was doing something that was very irrational.

"But ... it's very strange."