Chile's Supreme Court has reportedly stripped former military ruler Gen Augusto Pinochet of his immunity from prosecution on rights violations.
Gen Pinochet is also facing charges of embezzlement of public funds
The court's decision would open the way for Gen Pinochet to be charged with kidnapping and torture at the infamous Villa Grimaldi prison in the 1970s.
Chile's President Michelle Bachelet and her mother were among those tortured at the centre, in the capital Santiago.
Gen Pinochet's family say the 90-year-old is too ill to stand trial.
But this claim is disputed by some of the investigators looking into abuses which took place during the 17 years Gen Pinochet ruled with an iron grip.
"He's been stripped of immunity," a court source told Reuters news agency. Other agencies also quoted anonymous sources, saying an official announcement on the case may not be made until next week.
Gen Pinochet had enjoyed immunity from prosecution - a privilege he enjoyed under a law he himself imposed before leaving office in 1990.
The decision, which reportedly cannot be appealed, paves the way for Judge Alejandro Madrid to indict Gen Pinochet.
Thousands of people were tortured at the Villa Grimaldi, and many disappeared.
The case in question refers to the alleged kidnap of 36 political opponents and the torture of 23 of them.
President Bachelet and her mother have confirmed they were arrested months after the 1973 coup in which Gen Pinochet seized power and being tortured at Villa Grimaldi. They are not among the victims named in these charges.
This is just the latest twist of a long-running battle by Gen Pinochet's opponents to put him on the stand - never so far accomplished.
Gen Pinochet has previously been stripped of immunity to face human rights charges, only for the charges to be dismissed in the end. He is also facing charges of embezzling millions of dollars of public funds.
Gen Pinochet now lives in a house in the mountains outside Santiago and is rarely seen in public.