Two former leaders during Argentina's military rule have been found guilty of overseeing the systematic theft of babies from political prisoners. A court in Buenos Aires sentenced Jorge Videla to 50 years in prison and Reynaldo Bignone to 15 years, BBC news reported on Friday. They are already serving lengthy jail sentences for crimes committed under military rule, between 1976 and 1983. At least 400 babies are thought to have been taken from their parents while they were held in detention centres. The verdict is the culmination of a trial that began in February 2011. In total, 11 people, most of them former military and police officials, were facing charges. Nine, including Videla and Bignone, were convicted in the case over the theft of 34 babies. Two were found not guilty. Videla, 86, received the maximum sentence as he was held criminally responsible for 20 of the thefts. The court said Videla was guilty of the "systematic abduction, detention and hiding of minors under the age of 10". Victims' groups nevertheless welcomed the latest verdicts as a confirmation of the defendants' guilt for what many consider as the most heinous crimes committed under military rule. Relatives of the stolen babies, and those who were abducted themselves, described the verdicts as 'historic.'