Spain will extradite a former Argentine policeman wanted for the killing of writer and leftist guerrilla Rodolfo Walsh.
Walsh was gunned down on a Buenos Aires street in 1977 by a military death squad.
Juan Carlos Fotea will be handed over to Argentina to face charges of torture and human rights abuses, Madrid government said in a communique.
Mr Fotea is one of several former members of the Argentine security forces wanted for the killing of Walsh, a prominent writer who had gone underground as a member of the Montoneros guerrilla group after Argentina's military coup in 1976.
Spanish Judge Baltasar Garzon lodged charges against Mr Fotea in 1998, but an Argentine judge asked for his extradition last year.
Walsh was intercepted on a street in central Buenos Aires on March 25th, 1977, the day after he had published "An Open Letter to the Military Junta".
The letter protesting human rights abuses was praised as "a jewel of universal literature" by Nobel prize winning novelist Gabriel García Márquez, a fellow founder of Cuba's Prensa Latina news agency.
The military had orders to capture Walsh alive, but he was armed and returned fire before being shot dead. His body has never been found.
Walsh had been in mourning for his oldest daughter, Maria Victoria, also a Montonero, who had been killed in another shoot-out just months before and whose "short, hard, marvellous life" he had celebrated in an earlier letter.
Born in Patagonia of Irish descent, Walsh was a short story writer and investigative journalist whose works Operation Massacreand Who killed Rosendo?about Argentina's violent politics had earned him many enemies.
After the return of democracy in 1983, he became an emblem for campaigners seeking justice for the estimated 30,000 people who were kidnapped and killed during military rule.
His surviving daughter, Patricia Walsh, was elected to Argentina's Congress on a leftist ticket and in 2002 proposed a bill to scrap laws which restricted prosecution of military human rights abusers. The laws were overturned in 2005.