A number of people were seriously injured when a train derailed on Wednesday morning on the east coast of Scotland, First Minister Nicola Sturgeon said, as she declared a major incident.
Dark smoke billowed from a woodland area at the bottom of a valley near Stonehaven, just south of the oil city of Aberdeen, after the ScotRail train derailed following heavy rain overnight.
Two air ambulances and about 30 emergency service vehicles could be seen in a field just above the scene of the derailment.
Prime Minister Boris Johnson said he was saddened to learn of the "very serious incident" in Aberdeenshire and his thoughts were with all those affected.
The Press Association news agency, citing unnamed sources, reported that the driver of the train was feared dead and there were fears of another fatality. There was no immediate confirmation from officials.
"Although details are still emerging I am afraid to say there are early reports of serious injuries," Sturgeon said.
"This is an extremely serious incident. I've had an initial report from Network Rail and the emergency services and am being kept updated. All my thoughts are with those involved."
Police received reports of a train derailing near Stonehaven, 15 km (9 miles) south of Aberdeen, at 0940 a.m. on Wednesday.
The BBC reported that the train was made up of two locomotives, one at the front and one at the back, and four passenger carriages. It said the front locomotive and three of the carriages had left the track and were sitting on a river embankment.
Stonehaven and the surrounding area had been hit by floods in recent days after torrential rain and some reports suggested a landslide may have played a part in the derailment, although that was not confirmed by the authorities.
"Emergency services are currently in attendance and the incident is ongoing," a Police Scotland spokeswoman said.
Britain has one of Europe's lowest rates of fatal rail accidents, with a stronger safety record than Germany or France in recent years, according to Eurostat data that includes unauthorised people on railway tracks and at level crossings.
European railways are very safe for rail passengers, with just 13 deaths across the European Union's 28 member states in 2018, according to the most recent available data from Eurostat. One of those was in Britain.
The worst rail disasters in Britain in recent decades were a 1999 collision between two trains at Ladbroke Grove, in London, in which 31 people died, and a 2001 accident near Selby in Yorkshire, northeast England, in which 10 people died after a car ran onto the track and was hit by two trains.