A former senior policeman said on Thursday that a criminal investigation into the Hillsborough stadium disaster must take place after a probe found police tried to blame fans for the 1989 tragedy. Richard Wells, who was in charge of South Yorkshire Police from 1990 to 1998, said it was \"absolutely essential\" that a criminal probe be held into the way the police handled the disaster in which 96 Liverpool fans died. As the ramifications of the damning report into the disaster became clear, Football Association (FA) chairman David Bernstein offered \"a full and unreserved apology\" to all those affected. However, Bernstein\'s statement only came after relatives had demanded the FA apologise for awarding the match to Hillsborough in Sheffield, south Yorkshire, even though the stadium did not have a valid safety certificate at the time. After the report was published on Wednesday, the FA initially issued a statement welcoming the findings but offered no apology over the events at the match between Liverpool and Nottingham Forest 23 years ago. But Bernstein went further, saying: \"We are deeply sorry this tragedy occurred at a venue the FA selected. \"This fixture was played in the FA\'s own competition, and on behalf of the Football Association I offer a full and unreserved apology and express sincere condolences to all of the families of those who lost their lives and to everyone connected to the city of Liverpool and Liverpool Football Club.\" The report found that senior police officers had mounted a concerted campaign to cover up failings in the worst disaster in British football history. In the most heart-rending of the findings, the independent panel found that 41 of the 96 who died -- often from suffocation as they were crushed -- might have survived if the emergency services\' response had been better coordinated. Prime Minister David Cameron apologised to the families of the dead and injured following the publication of the report, saying they had suffered a \"double injustice\". Cameron said Attorney General Dominic Grieve would review the findings as soon as possible and decide whether to apply to the High Court for new inquests into the deaths to be held. The original inquests in 1990 and 1991 recorded verdicts of accidental death. Relatives of the victims of the disaster have vowed to push for those responsible to face justice. Liverpool\'s manager at the time of the disaster, Kenny Dalglish, who attended a vigil in the city on Wednesday, said on Twitter: \"Very positive outcome. 23 years waiting for the truth next step justice.\" A former British interior minister, Jack Straw, claimed that the police\'s reaction to the disaster had illustrated the \"culture of impunity\" created by the then Conservative government of Margaret Thatcher. In words that angered Conservatives, the senior Labour politician said the police felt they could \"rule the roost\" in the years after the 1984 miners\' strike in which they played such a crucial role on behalf of Thatcher. Straw expressed regret that a review he ordered in 1997 had failed to \"get to the bottom\" of the tragedy or expose the police cover-up revealed by Wednesday\'s report. But he said the police in the mid-1980s \"really were immune from outside influences and they thought they could rule the roost, and that is what we absolutely saw in South Yorkshire\".