An investigation has been launched after a woman was dragged along a London Underground platform and into a tunnel.
The 78-year-old woman suffered serious injuries after her bag became trapped between the doors of a train at Notting Hill Gate station, west London.
She was unable to free the bag or let go of it before the train departed despite being helped by others, accident investigators said.
Passengers who saw the woman in distress activated emergency alarms on the westbound Central line train and the driver applied the brakes.
But six of its eight coaches were already in the tunnel by the time the train came to a standstill.
Emergency services and London Underground's emergency response unit rescued the woman from the space between the underside of the train and the tunnel wall.
She is still recovering in hospital following the incident on January 31.
The Rail Accident Investigation Branch is seeking witnesses to help with its investigation, which aims to determine the sequence of events.
The process of checking whether it is safe for a train to depart and the door's obstacle detection system will also be considered during the inquiry.