David Cameron has apologised for the "double injustice" suffered by families of the victims of the Hillsborough disaster.
The Prime Minister was addressing Parliament about a new inquiry's findings - which he described as "harrowing" and "deeply distressing".
"What happened that day was wrong," he told MPs, ahead of the report's official release.
"On behalf of the government, and indeed of our country, I am profoundly sorry that this double injustice has been left uncorrected for so long."
Ninety six Liverpool supporters died in a crush at Sheffield Wednesday's Hillsborough stadium on April 15, 1989, where their team were to meet Nottingham Forest in an FA Cup semi-final.
The newly published documents say police and emergency services made "strenuous attempts" to deflect the blame for the disaster onto innocent fans.
Introducing the report to the Hillsbrough families at the Anglican Cathedral in Liverpool, Bishop James Jones, the Bishop of Liverpool and chairman of the panel, said:
"The documents disclosed to and analysed by the panel show that the tragedy should never have happened.
"There were clear operational failures in response to the disaster and in its aftermath there were strenuous attempts to deflect the blame onto the fans.
"The panel's detailed report shows how vulnerable victims, survivors and their families are when transparency and accountability are compromised.
"My colleagues and I were, from the start of our work, impressed by the dignified determination of the families."