Liverpool manager Brendan Rodgers has joined the UK police watchdog in appealing for fans present at the 1989 Hillsborough disaster to help a new investigation.
The Independent Police Complaints Commission (IPCC) put out a plea for witnesses on Wednesday as it examines police conduct in the aftermath of the tragedy with a view to bringing possible criminal charges.
Some 96 Liverpool supporters were crushed to death in an over-crowded section of terracing at the FA Cup semi-final between Liverpool and Nottingham Forest, played at Sheffield Wednesday's Hillsborough ground on April 15, 1989.
Around 12,000 fans gave evidence to West Midlands Police as part of an original investigation into the tragedy 24 years ago.
But the IPCC has unearthed discrepancies between that evidence and other statements that appear to have come from the same supporters.
An independent report published last September found that 164 police statements had been altered after the disaster - 116 of which were changed to remove negative comments about the policing of the match.
The IPCC wants to establish whether fan statements have also been tampered with.
Rodgers said: "I would ask all the supporters who gave those witness statements to get in touch with the IPCC.
"You've also got, on our club website, an opportunity for supporters to be directed on the right route. It's so important, this year. It's very important for the families of all the victims of Hillsborough - for their fight for justice.
"If we can get all those statements in, I know people will be reliving difficult memories, but it's something that will continue their fight for justice."
The West Midlands force took the fan statements in 1989 after being appointed to look into the way that South Yorkshire Police handled the Hillsborough disaster.
No individuals or organizations were prosecuted as a result of that original inquiry, but the Hillsborough Independent Panel report, which came out 12 months ago, highlighted a cover-up by the police and emergency services, while exonerating fans of any blame.
Since then, the victims' original inquest verdicts of accidental death have been quashed, while two separate investigations have been set up to examine the conduct of the police and emergency services.
The IPCC is examining police conduct in the aftermath of the Hillsborough disaster. A second investigation, focusing on possible criminal behaviour by any people or bodies with responsibility for fan safety at Hillsborough, is being headed up by former Durham chief constable Jon Stoddart.