(CNN) -- At least one explosion rocked government buildings in Oslo, Norway, on Friday, state TV and witnesses said.
Windows in several buildings had been blown out, and people were in the street bleeding, state TV broadcaster NRK said on its website.
There are conflicting reports about whether a second blast followed the first, which occurred mid-afternoon in the center of the Norwegian capital.
One explosion happened near a government building housing the office of Prime Minister Jens Stoltenberg, said Linda Reinholdsen, a reporter for Norwegian state broadcaster NRK. Another hit near the Norwegian parliament, she told CNN.
Several buildings in Oslo were on fire, she said, and smoke was pouring from them.
Walter Gibbs, a journalist with Reuters, said he saw eight injured people, including two or three with serious wounds and one who looked dead.
Gibbs said he believes one explosion happened on an upper floor of a main government building. He said it blew out every window on the side of the building.
The blast also severely damaged the Oil Ministry and left it in flames, he said.
Reuters reported that Stoltenberg was safe.
Nick Soubiea, an American-Swedish tourist in Oslo, told CNN he was less than 100 yards from the blast, which he described as deafening.
"It was almost in slow motion, like a big wave that almost knocked us off our chairs," he said. "It was extremely frightening."
He said the streets were crowded with people trying to get away from the center of the city. "There are people running down the streets, people crying, everyone's on their cell phones calling home," he said.
A hotel worker in Oslo's Grand Hotel, about a five-minute walk from the government building, said everyone in the hotel felt and heard the explosion, which felt like someone was shaking the entire building.
"It's crazy," she said, not wanting to be identified because she is not authorized to speak to the media on behalf of the hotel. "This happens in the big world, not in Oslo. I'm shocked."
Vivian Paulsen, media adviser for the Norwegian Red Cross, lives 20 minutes away from the center of Oslo in the northern outskirts of the city. She said she heard a "huge blast."
"I heard the big bang, I didn't think it was anything serious. I can still see smoke coming up from the place," she said, watching from her apartment balcony. She also heard sirens and ambulances.
As for Oslo, she said what others have been saying: Events like this don't happen in the northern European capital.
"There's occasional arrests of terror suspects we read about in the paper, or people planning something. I can hear ambulances and sirens."
http://edition.cnn.com/2011/WORLD/europe/07/22/norway.explosion/http://cnn.com/video/?/video/world/2011/07/22/bpr.norway.oslo.explosion.cnn
Topic: Giant blast hits government buildings in Oslo, Norway