The former head of Argentina's air force and two ex-subordinates are on trial for alleged abduction and disappearance of activists during the South American nation's 1976-1983 dictatorship.

Omar Graffigna, who today is 90 years old, is accused of abducting activist couple Patricia Roisinblit and Jose Manuel Perez Rojo in 1978.

Roisinblit was eight months pregnant when she, Perez Rojo, and a 15-month-old daughter were taken to a clandestine detention center. What happened to the couple is unknown.

Guillermo Perez Roisinblit, the son Roisinblit gave birth to during detention, is a plaintiff in the trial that began this week. He was adopted by another family.

Rights groups estimate 30,000 people were killed or disappeared during the dictatorship. Hundreds of former military officials have been convicted.