A Chilean judge has indicted five top intelligence officials from the Pinochet era military government over the murder of a former general, Carlos Prats.
Manuel Contreras was a secret police commander
Alejandro Solis also ordered the five to be arrested and held in detention.
General Prats was the head of the Chilean army under President Salvador Allende, who was overthrown by General Augusto Pinochet in a bloody coup in 1973.
He and his wife, Sofia Cuthbert, were killed a year later when their car was blown up in the Argentine capital Buenos Aires.
Judge Solis indicted General Manuel Contreras and Brigadier Pedro Espinoza, commanders of the secret police of Pinochet's 1973-90 dictatorship, known as the Dina, on homicide charges.
He also indicted General Raul Iturriaga and his brother, Jorge, on homicide charges. Brigadier Jose Zara was indicted as an accomplice, according to Chilean newspaper El Mercurio.
The men, all now retired, reject the charges. They say the American Central Intelligence Agency (CIA) was behind General Prats' murder.
Previous judicial investigations placed the blame for the bomb at the feet of Michael Townley, an American who worked for the Dina. Mr Townley now lives under a new identity in the United States.
Allende's overthrow is still a painful memory
This is the first time the murders have been investigated by Chilean authorities. Proceedings began after Buenos Aires requested the extradition of the five men and Mr Pinochet himself in relation to its investigation.
In turning down the extradition request, the Chilean court ruled the eventual trial should take place in Chile.
Mr Pinochet has not been included in the case because the Supreme Court previously ruled that ill health precluded him from standing trial.
Last week the current US Secretary of State Colin Powell acknowledged the US role in the 1973 coup in Chile.
In an interview on the US Black Entertainment Television network, a question was asked about why Washington sees itself as the "moral superior" in the Iraq conflict.
The Chilean coup was cited as an example of US intervention that went against the wishes of the local population.
"With respect to your earlier comments about Chile in the 1970s and what happened with Mr Allende, it is not a part of American history that we're proud of," Mr Powell answered.
The weekend papers in Chile hailed the news as the first time the US Government had conceded a role in the affair.