Judges in Argentina have convicted three former navy officers of summarily executing 16 political prisoners, and called on the U.S. to extradite a fourth suspect living in Miami.

The "Massacre of Trelew" in 1972 presaged the violence leading to Argentina's bloody dictatorship four years later. The inmates were shot even though a judge publicly guaranteed their safety.

The judges gave life sentences for murder to Emilio del Real, Luis Sosa and Carlos Marandino. Former navy Capt. Roberto Bravo was charged with them, but a U.S. judge denied his extradition, saying Argentina's military had absolved him.

Judge Enrique Guanziroli called it long-delayed justice, but their lawyers are preparing an appeal, saying killings don't qualify as crimes against humanity.