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 has been taken to hospital.
But the police are looking for another man who disappeared in the landslide. When the landslide occurred, he was working on maintenance of the railway in the area.
He is feared to have been killed, according to Norwegian media.
There is an obvious risk that a life has been lost, says Johan Mannsåker to the newspaper Dagbladet.
Norway's Transport Minister Jon-Ivar Nygård describes the incident as dramatic in an email to the news agency NTB.
"I have ensured that all available resources have been mobilized", he writes.
Two residences in the area – by 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 the landslide masses start to move. Suddenly it collapsed and the car in front of me disappeared, says truck driver Mats André Afreth to the Norwegian TV channel Tv2.
Afreth was forced to make an emergency stop with his vehicle and when he backed up, it started 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.
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. And 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 during the weekend due to railway maintenance, including lime and cement stabilization, according to the Norwegian railway authority to Aftenposten.
Fact: Quick clay
TT
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 ends up in 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
