Chilean police have arrested some 25 former officials for allegedly helping to purge critics of former ruler General Augusto Pinochet.
A judge on Tuesday issued 129 warrants against former members of Chile's secret police agency, Dina.
They are accused of taking part in the killings and disappearances of dozens of leftists and opposition activists.
Since Gen Pinochet left power in 1990, there have been frequents arrests of his agents - often dividing opinion.
Tuesday's warrants, issued by Judge Victor Montiglio, named dozens of former military and security officials who had never faced charges before.
Anti-Pinochet activists have broadly supported the move to punish those responsible for torture and murder.
But many Chileans have questioned the wisdom of continuing to chase down suspects, saying many of those now being arrested were little more than foot-soldiers.
Thousands of activists were killed or disappeared during the 1973-1990 rule of Gen Pinochet.
The arrest warrants cited various Dina operations to track down Pinochet's opponents, such as Operation Condor - a long-running campaign launched in the mid-1970s to hunt down and kill left-wingers.
Condor was a continent-wide operation, also backed by the rulers of Argentina, Brazil, Bolivia, Paraguay and Uruguay.
Another incident cited in the court papers was Operation Colombo, referring to the 1975 killing of 119 Chilean activists.
The judge also cited the case of 10 communists who disappeared in 1976.