The most likely cause of Monday’s frontal collision between two passenger trains in western Switzerland was an error on the part of one driver, a spokesman for the local police force investigating the crash said.

Jean-Christophe Sauterel, spokesperson for Vaud cantonal police, said "the current hypothesis is that the train coming from Payerne ignored a signal." Further fatalities have not been ruled out as work continues on separating the two trains.
 
The initial investigation has found that the 54-year-old conductor of the train from Payerne saw the oncoming train, activated the emergency brake and evacuated his post, per Swiss Federal Railways protocol.

A train driver was killed and 35 people injured, five of them seriously, in the collision at the rural station of Granges-Marnand on a single-track section of the regional line between Lausanne and Payerne.

The body of the 24-year-old driver was recovered overnight by rescue workers, having been trapped inside the cab of one of the trains. According to officials, he was a French national who lived in Payerne.

Police officials said at a press conference that the front of the train coming from Lausanne impacted by eight metres, so they "could not rule out the possibility that a deceased passenger could still be inside". Rescue work continues on-site.

Twenty-six people were brought to area hospitals for treatment. Two adults and one child remained hospitalised Tuesday, according to a hospital spokesperson, none with life-threatening injuries.
  
Trains run on a single track near the small town of Granges-Marnand, with a two-track crossing point at the station. The train coming from Lausanne - a faster regional train - should have passed through the single-tracked area first, and the commuter train from Payerne was to wait at the station so they could pass each other. However, when the faster train entered the single-track area, the train from Payerne had already left the station, leading to a head-on collision.
  
A number of ambulances and a helicopter were called in, and police and fire engines were also present at the site. 
 
The Swiss Federal Railways set up a hotline for relatives and friends.
  
Authorities have launched an investigation into what happened, with the Swiss Accident Investigation Board taking the lead.
 
In January, 17 people were injured when two trains collided in the northern Swiss town of Neuhausen am Rheinfall. The cause of that crash was found to be that one of the trains had left the station too early without heeding a warning signal. 

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