MADRID, Spain (CNN) -- Spain will extradite former Argentine officer Ricardo Miguel Cavallo to his homeland, where he faces charges of human rights abuses during the South American country's "Dirty War" more than two decades ago, a Spanish court ruled Friday.
Cavallo, who is in his 50s, is expected to leave Spain in a matter of "hours, or at the most, days," a court spokeswoman told CNN.
An attorney, however, said Friday he plans an appeal of the decision.
Although the court has sought to bring dozens of former Argentine officers to Spain to face justice, Cavallo -- who has denied all charges -- is among a small number it actually holds in custody.
Cavallo was a navy lieutenant at the Navy Mechanics School in Buenos Aires, where many opponents of the Argentine right-wing, military governments in the 1970s and 1980s disappeared or were killed, according to Spanish court documents and human rights groups.
He has been in Spanish custody since 2003, when he was extradited from Mexico on a warrant for human rights abuses.
His defense lawyer argued that year that Spain had no jurisdiction in his case, which is part of the Spanish court's years-long investigations into rights abuses in Argentina during the former military governments.
According to the court document outlining the Spanish prosecutor's charges, Cavallo was "fully integrated into the development of the plan of repression and extermination."
In becoming involved in the case, Spain tested the legal principle called "universal justice," in which the Spanish court considers that it has jurisdiction to try cases of human rights abuses committed elsewhere.
But in recent years, Argentina has opened its own judicial proceedings into the alleged abuses, and since at least late 2006, Spain has been trying to extradite Cavallo to Argentina to face justice there.
Cavallo's efforts to avoid extradition ended Friday, when a three-judge panel at the National Court ruled that the extradition -- approved three weeks ago by the Prime Minister's Cabinet -- could occur.
Immediately after that, another judge signed the necessary order and sent it to international policing agency Interpol.
Human rights groups have identified the Navy Mechanics School as a prime detention and torture center under the former military regime, which sought to neutralize its leftist opponents.
"Of the 30,000 people who disappeared during the military dictatorship, some 5,000 of them were detained, at least for a time, at the Navy Mechanics School," the court document said. E-mail to a friend