Dr Alan Billings, South Yorkshire Police and Crime Commissioner, said: “I have been made aware of a loss of data from the force’s storage systems and the work that is taking place to recover the data.
“There may be implications for victims and witnesses and the wider criminal justice system as some of this footage may be evidence in upcoming court cases. The force is working through the implications and direct contact is being made with those affected.
“This incident is disappointing and concerning and the police need to understand quickly what has happened and why.
“I have been briefed by the Deputy Chief Constable and will continue to receive updates as the work continues to recover the data.
“I will also be seeking a full explanation as to how this incident occurred and what measures will be put in place to prevent it happening again.”