An Argentine court has started hearing evidence in the first trial in 20 years of a former member of the security forces on charges linked to the 1976-83 dictatorship's "dirty war" against opponents.
Retired police official Miguel Etchecolatz, 76, is charged with forced disappearances, torture and homicide, part of what rights groups say were 30,000 deaths during the military regime.
He is the first former officer to be tried since the Supreme Court struck down amnesty laws last year.
Etchecolatz sat handling rosary beads as he listened to a judge read the charges of illegal arrest, torture and six counts of homicide in La Plata, capital of Buenos Aires province, where he was chief of police detectives.
He was jeered by human rights activists and relatives of the disappeared as he left the courtroom in La Plata, 37 miles southeast of national capital Buenos Aires. The trial is expected to last several weeks.
"We are finally seeing the results of last year's historic Supreme Court decision," said Jose Miguel Vivanco, Americas director at Washington-based Human Rights Watch. "After years of impunity, the prosecution of those responsible for these crimes is at last moving forward."
Etchecolatz was sentenced to 23 years in 1986 on many charges of forced disappearances - illegal arrests carried out by the military regime as it tried to purge dissidents. Most of the bodies of the disappeared were never found.
However, he was released the following year due to the enactment of laws that shielded all but the former military government's commanders from prosecution.
The laws were passed by then-President Raul Alfonsin to quash military rebellions following the trials of former junta leaders, who were themselves pardoned in the 1990s by then-President Carlos Menem.
Human rights groups and lawyers complain that courts have been slow to try up to 1,500 officers since immunity ended last year.
One former officer awaiting trial is Alfredo Astiz, who was convicted in absentia in a French court and sentenced to life in prison in 1990 for the murder of two French nuns. No date has been set for his trial.
Etchecolatz was sentenced in 2004 on separate charges - not covered by the amnesty laws - of kidnapping babies born to mothers in captivity. He has been serving the sentence at home, as Argentine law allows for convicts more than 70 years old.