Three people confirmed dead after passenger train derails in Scotland
It is thought the train hit a landslide after heavy rain and thunderstorms which caused flooding and travel disruption across Scotland.
The incident involved the 06:38 ScotRail service from Aberdeen to Glasgow Queen Street.
British Transport Police said: "Very sadly, despite the best efforts of paramedics, we can confirm that three people have been pronounced dead at scene."
First Minister Nicola Sturgeon said her thoughts were with all those involved in the incident.
She said the derailment had happened in "a very difficult location for emergency services to access".
She added: "I know and appreciate that there will be many families who will be anxious if they believe they had relatives who were on that train.
"We will do everything we can to make sure the emergency services are supported, that families are supported."
Prime Minister Boris Johnson said: "I am saddened to learn of the very serious incident in Aberdeenshire and my thoughts are with all of those affected. My thanks to the emergency services at the scene."
An investigation is now under way to determine the cause of the crash.
Heavy rain and thunderstorms had caused flooding in the area and across Scotland ahead of the derailment.