The former head of Chile's secret police, Gen Manuel Contreras, says he has details of the fate of 580 people who disappeared during military rule.
More than 1,000 people disappeared under Pinochet
Gen Contreras handed in a document to the Supreme Court which he says contains details of their whereabouts.
He says he made inquiries about the fate of detainees named in the report of Chile's official torture commission.
Chilean human rights groups have so far made no comment and it is unclear how much of the information is new.
The handover of the document comes six months after Chile's National Commission on Political Imprisonment and Torture published its report - the first-ever major investigation into torture and detention during the 17-year regime.
The study was based on interviews with 35,000 former prisoners.
Gen Contreras was in charge of the secret service, the Dina, during the entire duration of the military government from 1973 to 1990, reporting directly to the country's president, Gen Augusto Pinochet.
Gen Pinochet took power in a coup on 11 September 1973, ousting the democratically-elected socialist President Salvador Allende.
Gen Contreras, who has been convicted twice for human rights abuses, said Gen Pinochet was responsible for the repression of left-wing activists during his period of government.
Last week, the Supreme Court indefinitely suspended a deadline it set earlier this year for an end to investigations into alleged human rights abuses.
The ruling means judges will be given extra time to investigate and charge suspects in more than 150 cases, some of them involving Gen Pinochet.