Criminal charges over the Hillsborough disaster are back on the table as a fresh police investigation is launched.

The deaths of the 96 Liverpool fans at the 1989 FA Cup semi-final is the focus of the new inquiry, led by former Durham Chief Constable Jon Stoddart, Home Secretary Theresa May said.

Families welcomed the move as the "first step towards accountability" but urged all authorities to work together to ensure justice.

The announcement came as High Court judges quashed the original accidental death verdicts on the disaster which occurred 23 years ago and ordered a fresh inquest. Both decisions follow a damning report from the Hillsborough Independent Panel in September, which laid bare the attempts to shift blame for the tragedy onto its victims.

Commenting on the new police investigation, Jenni Hicks, who lost her teenage daughters Sarah and Victoria at Hillsborough, said "accountability has to come now". She said: "After the truth we had in September it has to be followed up with accountability, and I think today is the first step of that, which is brilliant."

Mr Stoddart will work closely with the previously announced Independent Police Complaints Commission (IPCC) investigation into police conduct in the aftermath of the disaster. Both investigations will be conducted from the same office in Warrington, Cheshire.

The Stoddart investigation will be into a range of agencies outside the IPCC's remit but in order to maintain independence, the IPCC will look at the actions of police officers in relation to the deaths. In addition to announcing a new investigation, a Liaison Board will be established to bring together all organisations working on behalf of the Hillsborough families.

Ms Hicks's ex-husband Trevor, chair of the Hillsborough Family Support Group, said he is encouraging all sections of the investigation to work together. He said: "We've said all along that we wanted joined-up writing, if you like. We want them all to work together. There's a common cause and that's justice for the families and how we get that."

Mr Stoddart will be able to recruit investigators and staff to his team but will not be allowed to employ officers or former officers who have prior connection to the Hillsborough disaster. He is also unable to recruit any officers or former officers who worked in West Midlands, South Yorkshire or Merseyside police forces.

The investigation may trigger criminal prosecutions, the Home Secretary said, which will be the responsibility of the Director of Public Prosecutions and the Crown Prosecution Service.