A person in a car ended up in the water when the landslide occurred at nine o'clock in the morning. He was picked up by boat and taken to hospital.
The rescue service has also been searching for another man who disappeared in the landslide. At 5 pm came the message that he is believed to have died.
"There will now be a search for a presumed deceased. It is about a Danish man who worked at the site," the police write in a press release, according to the news agency NTB.
The man was working on maintenance of the railway in the area.
Norway's Transport Minister Jon-Ivar Nygård describes the incident as dramatic in an email to NTB.
"I have ensured that all available resources have been mobilized," he writes.
Two residences in the area – at Nesvatnet in Levanger municipality – have been evacuated and the public is warned against being in the vicinity of the landslide. A longer stretch of railway has also been affected and is partially hanging in the air and down in the water.
"The road had disappeared"
I was driving behind a car when I saw that the landslide began to move. Suddenly it collapsed and the car in front of me disappeared, says truck driver Mats André Afreth to Norwegian TV2.
Afreth was forced to make an emergency stop with his vehicle and when he backed up, it began to collapse in front of the car.
It was not a pleasant feeling. We are talking about a few meters, he says.
Norwegian police are seeking contact via their website with motorists who were driving south on the road section in the minutes before the landslide and who had a dashcam turned on.
Sissel Buchholdt lives right next to the accident site. She was sitting by the window and drinking coffee when she saw the landslide occur.
It did not come as a surprise. We expected this to happen, but we did not know when, she says to NRK.
Clay risk area
The area has previously been identified as a risk area when it comes to so-called quick clay by Statens vegvesen, Norway's equivalent to the Swedish Transport Administration. Gustav Grimstad, professor of geotechnics at the university NTNU in Trondheim, warns that the landslide can grow in the coming days if there is more clay around the hole that has now appeared.
Quick clay is a special type of clay that can lose its stability if it is exposed to vibrations, rain or increased load.
Train traffic on the Nordlandsbanan through the landslide area was closed over the weekend due to railway maintenance, including lime and cement stabilization, says the Norwegian railway authority to Aftenposten.
Quick clays are normally relatively stable, but can become very loose if they are exposed to vibrations or increased load.
Several of the major landslides that have occurred in western Sweden are of the quick clay type.
When the clay loses its stability, it enters a fluid state and the cohesive force between the clay particles is lost. This can lead to major landslides.
Quick clay is found in Scandinavia, North America, and Russia, where it was formed in connection with the large inland ice sheets. Areas with high salt levels are most vulnerable.
Source: SGU
