Margaret Thatcher was informed by an unnamed senior Merseyside police officer that "drunken Liverpool fans" were to blame for causing the Hillsborough disaster, according to confidential government documents leaked to the BBC.
The official inquiry into the disaster at the 1989 FA Cup semi-final which left 96 fans dead ruled it was caused by a failure in crowd control by South Yorkshire police.
Previously secret government and police documents relating to the disaster are being reviewed by the Hillsborough Independent Panel, set up in 2009, but they are not expected to be made available to the families of those who died or to the public until the autumn.
However, among the leaked documents is a letter sent to the then prime minister from a member of her policy unit in Downing Street four days after the disaster, which details a different initial version of events put forward by the chief constable of Merseyside police, the late Sir Kenneth Oxford, and some of his senior colleagues in the immediate aftermath.
According to the letter, made public by the BBC Radio 4's The World at One, the Merseyside chief constable told officials: "A key factor in causing the disaster was the fact that large numbers of Liverpool fans had turned up without tickets. This was getting lost sight of in attempts to blame the police, the football authorities, etc."
The letter went on to report that a senior member of the Merseyside police directly blamed supporters: "One officer, born and bred in Liverpool, said that he was deeply ashamed to say that it was drunken Liverpool fans who had caused this disaster, just as they had caused the deaths at Heysel." This officer is not named.
The documents also report that the chief constable "deplored the press's morbid concentration on pictures of bodies. He was also uneasy about the way in which Anfield was being turned into a shrine."
Sheila Coleman, from the Hillsborough Justice Campaign, told the BBC: "We are really concerned that the emphasis is totally on Merseyside police here and not on South Yorkshire police, and that makes us very suspicious of how this information was leaked.
"We find it a strange coincidence that this information was leaked only days after we found out the [Hillsborough Independent] panel are not going to report until the autumn."