The trains were about one kilometer apart

– It is rare that there is only one cause of an accident, says the department director.

The National Accident Investigation Board published pictures from the train accident in Arna on Sunday. They have now finished the work on site, says department director Ida Hogganvik Grøndahl.

– We have received various forms of information, which we have to put together in a bigger picture, she says.

She says it is too early to come up with a theory about what happened.

– It is rare that there is only one cause of an accident. It is always made up of several factors, she says.

The police have given two people the status of suspect after the accident.

Will examine safety mechanism

The accident happened on Friday evening, when a freight train on its way from Bergen ran a red light and derailed at the entrance to the Arnanipa tunnel at Arna station.

The Accident Investigation Board has previously stated that the derailment was caused by the goods train being led off the track it was on, and onto a short siding. This is a safety mechanism.

Grøndahl says that the Accident Investigation Board will, among other things, investigate whether the safety mechanism worked as it should.

A track in the tunnel

At the same time as the goods train derailed, there was another train in the tunnel. This train came from Oslo.

The Accident Investigation Board previously did not want to say how far apart the two trains were from each other. On Sunday, they stated that the distance was about one kilometre.

There is only one track in the tunnel.