New footage of the Hillsborough disaster shows victims being carried away from the tragedy by fellow fans.
The videos have been released in the latest appeal to trace witnesses who have still not been identified.
The disaster caused the deaths of 96 people at an FA Cup tie between Liverpool and Nottingham Forest at the Sheffield stadium in 1989.
The deaths are the subject of an ongoing new inquest.
In the first of two clips, four people carry a casualty across the concourse area behind the West Stand, through exit gate C and to a waiting ambulance.
The four witnesses who are sought are lettered A, B, C and D on the footage.
Video: One of two video clips released of the disaster
In the second, another person is carried through the same area, again to an ambulance. The witnesses needed are labelled E, F, G H and I.
Video: The second shows a larger group of people carrying someone
Earlier this year, investigators said they still needed to trace dozens of people, many of them Forest fans.
Coroner Sir John Goldring and the victims’ families requested the latest appeal, which is the first to involve video footage.
Anyone who recognises the people in the footage is asked to contact Operation Resolve on 0800 0283284.
Video: Hillsborough witness and Forest fan John West, right, talks about the tragedy
