Here are the key timeline moments in the lead up to the accident and its aftermath.
6.38am: The Abellio ScotRail Aberdeen to Glasgow Queen Street service departs on time amid reports of deteriorating weather conditions in the north east of the country. Severe thunderstorms occurred in the area on the night of August 11, prompting weather alerts from the Met Office, and causing flooding across Aberdeenshire.
6.53am: The service calls at Stonehaven railway station.
7am: The train stops for a landslip between Stonehaven and Carmont signal box.
9.30am: The train is held up for more than two and a half hours before being moved onto the northbound track to be sent back to Stonehaven.
9.37am: The train, travelling at 73mph runs into debris impact with the debris derailed the train, which then travelled a further 70 metres before striking the parapet of the bridge.
9.38am: A rail worker uses WhatsApp to alert the emergency services.
9.43am: Police Scotland and British Transport Police are notified. PC Liam Mercer, of Stonehaven police station, was first on the scene.
11.15am: A multi-agency response – including the Scottish Fire and Rescue Service, Scottish Ambulance Service, Scotland’s Charity Air Ambulance and HM Coastguard – are pictured working at the scene alongside police officers.
3.30pm: NHS Grampian sets up a help centre in Aberdeen for family and friends impacted by the crash as a formal investigation into the accident commences.
4.15pm: British Transport Police (BTP) confirm three people have died and six injured. The dead were later named driver Brett McCullough, 45, conductor Donald Dinnie, 58, and passenger, Christopher Stuchbury, 62.
8.17pm: The Queen sends a message of condolence, following on from Boris Johnson and Nicola Sturgeon.
August 12, 2021: On the first anniversary rail services across Scotland stopped for one minute at 09:43 to remember those who died.
August 14: Prince Charles visits the crash site and thanks emergency responders.
March 10,2022: The official report into the accident reveals a string of failings, placing much of the blame on Network Rail and contractor Carillion, which is labelled as “damning’ and “a watershed moment for rail safety” by union leaders.
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