Milani reportedly being questioned over the 1977 kidnappings of Pedro Adan Olivera and his son Ramon Alfredo Olivera, Delfor Brizuela, the human rights ombudsman for the northwestern province of La Rioja - where the retired general was detained - told the news agency AP.

A court office confirmed that Milan was transferred to a jail after testifying Friday before Judge Daniel Herrera Piedrabuena about the case.

The Oliveras say they were abducted and tortured by Milani and his men for alleged involvement in a leftist militant organization.

This was part of the 1976-1983 regime's "dirty war" on its opponents and their alleged collaborators in which 30,000 people were killed or disappeared.

Milani was previously charged with corruption in December over unanswered questions about where he got the money to buy a house in an upscale Buenos Aires suburb in 2010.

Milani was a lower-ranking officer during the 1976-1983 dictatorship and later rose to head the armed forces during the 2007-2015 term of former President Cristina Fernandez.

The court statement did not specify what role Milani played in the case of the Oliveras in 1977 or that of Matta a year earlier. He was charged with aggravated torture, illegal search and kidnapping.

The 62-year-old lieutenant general also is under investigation in at least one other human rights case. He also faces charges of illegal enrichment.

jbh/kl (AP, AFP, EFE)