A train carrying 200 passengers has been derailed by a landslide, causing several carriages to plunge into a ravine.
One of the carriages hanging off a steep ravine. Pic: Blick.chPictures from the scene show at least one carriage in a ravine and another hanging precariously from the tracks winding through mountains in the east of Switzerland.
Rescue helicopters could also be seen hovering over the eight-carriage regional train in the heavily forested region of Graubuenden.
Scores of passengers on the carriages that managed to remain upright were evacuated to safety and could be seen at the side of the tracks, walking to the nearby town of Tiefencastel.
A number of injured passengers were airlifted to hospital, while several others were treated for shock by paramedics.
Some passengers were rescued by helicopter. Pic: Blick.ch"Part of the train was derailed by a landslide," a spokesman for Rhaetische Bahn said, adding that he was unable to give further details immediately.
The train was travelling from the mountain resort of St Moritz to Chur when it was caught in the landslide between Tiefencastel and Solis, southeast of Zurich, at around 11.45am UK time.
Three carriages came off the tracks and plunged down the slope of the mountainous region following hours of rainfall earlier in the area.
Terrified passengers described moving to the rear of a carriage to stop it crashing over the edge.
Passengers were evacuated and walked to the nearest town. Pic: Blick.chOne told news website 20 Minuten: "We all rushed to the back of the carriage to put all of our weight there, so that it didn't tip into the abyss."
Another eyewitness, who was travelling with his wife and granddaughter to Basel, told Swiss website Blick.ch they were sitting behind one of the carriages that plunged into the ravine.
"There was an announcement that we should move into the rear car," he said.
Afterwards, all of those on board the train were told to get off it.
"We had to walk about a kilometre ... through a tunnel. The luggage is still on the train," he added.
Reports suggested there were no fatalities, but police said several passengers were injured.