A Chilean court has stripped former military ruler Augusto Pinochet of his legal immunity over the murder of his predecessor as army chief.
Human rights groups say Pinochet's regime killed thousands
The decision means he can be investigated for his alleged role in the killing of Gen Carlos Prats, who died in a car bomb attack in 1974.
Gen Prats, a symbol of opposition to the Chilean military government, had fled to Argentina.
It is the second case in which Gen Pinochet, 89, has lost his immunity.
In May, judges decided that he could be investigated in connection with Operation Condor - a conspiracy by six South American regimes in the 1970s to hunt down and kill their left-wing opponents.
Gen Prats and his wife, Sofia Cuthbert, were killed on 30 September 1974 when a bomb went off in their car as they were arriving at their Buenos Aires home.
A former Chilean secret service agent, Eduardo Arancibia Clavel, was sentenced to life imprisonment by an Argentine court in November 2000 for his direct involvement in the killing.
In Thursday's ruling, the Court of Appeal decided by 14 votes to 9 that Gen Pinochet should lose his legal immunity in the case.
The BBC's Clinton Porteous in Chile says the ruling is a blow for Gen Pinochet, who was in power for 17 years after a military coup in 1973.
The decision was welcomed by the Prats family, whose lawyer Pamela Pereira told La Tercera newspaper: "This opens a new line of investigation in the crime and will allow us to establish the real responsibility of Gen Pinochet and the others involved who are being prosecuted."
The general can still appeal against the decision in the Supreme Court.
Gen Pinochet, who also faces tax fraud charges and a money-laundering investigation, recently underwent medical tests and will find out soon whether he is fit to face trial.