(CNN) -- A top British police officer being investigated over a cover-up in connection with the death of 96 people in the Hillsborough stadium disaster in 1989 has resigned, his force said Wednesday.
Sir Norman Bettison was with South Yorkshire Police at the time of the crush at Sheffield's Hillsborough Stadium, and worked on an internal inquiry into what happened.
Bettison has been under growing pressure since an independent report published last month was heavily critical of the role played by the police and emergency services.
In response, Britain's police watchdog, the Independent Police Complaints Commission, launched a criminal investigation into police misconduct -- saying the report "revealed extremely serious and troubling issues for the police."
Bettison's resignation as Chief Constable of the West Yorkshire Police is effective immediately, the force said in a statement Wednesday. He had held the position since 2006.
Media attention and the investigation by the IPCC were "proving to be a huge distraction for the force," the West Yorkshire Police Authority said
Bettison said he had hoped to stay in his post to address the allegations against him, but was urged by the West Yorkshire Police Authority and others to stand down now.
"I do so not because of any allegations about the past, but because I share the view that this has become a distraction to policing in West Yorkshire now and in the future," he said.
Bettison said he had "always felt the deepest compassion and sympathy for the families" of the Hillsborough victims and he shares their desire to know the truth about what happened. "I have never blamed the fans for causing the tragedy," he said.
Bettison said he would cooperate fully with the criminal and IPCC investigations into the police handling of the disaster.
The crush at Sheffield's Hillsborough Stadium on April 15, 1989, has cast a lasting shadow over Liverpool and the surrounding Merseyside area.
The families of those killed and injured have battled for two decades to get to the truth about what happened on that awful day, with the report by the independent panel a key step along that road.
The Hillsborough Independent Panel found there had been "strenuous attempts" by police to deflect responsibility for the disaster to Liverpool fans by falsely claiming they were drunk and aggressive.
Its analysis also revealed that changes were made by South Yorkshire Police to police statements to remove and alter comments unfavorable to their organization.
As many as 41 of those crushed could have survived had the emergency services' response been better, the panel concluded -- something that the families of the victims had long suspected.
The tragedy occurred when thousands of fans were let through a gate into an already crowded standing area, leading many to be crushed against metal fences and concrete walls. Horrifying images from the scene showed panicked men, women and children pushed and trampled with nowhere to go as police lost control of the crowd.
The impact of English football's darkest day lives on in the tributes still paid by Liverpool to its lost sons and daughters, husbands and fathers.
But the tragedy also forced the sport to change on a national basis, and in a way still felt today, with stadiums modernized and made more family friendly, leading in turn to greater investment from sponsors and TV broadcasters.
CNN's Laura Perez Maestro contributed to this report.