UPDATE 1-Colombia's attorney general resigns over court refusal to extradite FARC leader

(Recasts story to add attorney general's resignation over extradition case)

BOGOTA, May 15 (Reuters) - Colombia's attorney general said on Wednesday he resigned in protest after a special court charged with prosecuting war crimes denied a U.S. extradition request for a former FARC leader accused of drug trafficking.

The Special Jurisdiction for Peace (JEP) tribunal prosecutes leaders of the Revolutionary Armed Forces of Colombia (FARC) guerrillas, who demobilized under a 2016 peace deal, as well as military officials for crimes committed during the country's five-decade internal conflict.

The JEP earlier on Wednesday ordered the release of Seuxis Paucias Hernandez, better known by his war alias Jesus Santrich, saying evidence provided by prosecutors did not allow the court to evaluate whether or when he allegedly conspired to move cocaine to the United States.

Because the JEP has jurisdiction over all crimes which took place during the war, Hernandez's extradition can only go ahead if the alleged crime took place after the accord, placing it within the remit of the regular justice system.

Hernandez was indicted over a year ago by a U.S. grand jury for conspiracy to export 10 tonnes of cocaine, worth $320 million in street value.

"This challenge to judicial order will not be endorsed by the undersigned. My conscience and my devotion to the rule of law prohibit it," Attorney General Nelson Humberto Martinez told journalists.

"For that reason I have presented my irrevocable resignation," he added.

Martinez, who has been beset by questions over his connections to the Latin America-wide Odebrecht corruption scandal, took office in 2016 and was meant to serve until 2020. He has denied any misconduct and recused himself from the investigation into Odebrecht.

The U.S. Embassy in Bogota said it had no immediate comment.

Separately, the FARC's political party on Wednesday accused the far right of assassinating its members, but pledged to continue reintegration.

The party, which kept its famous initials but changed its name to the Revolutionary Alternative Common Force, came a day after the shooting death of Jorge Enrique Corredor, the highest ranking ex-guerrilla to be killed since the deal.

"We won't hesitate to point the finger at right-wing and paramilitary sectors closely linked to state security agencies, who are behind these murders," FARC senator Pablo Catatumbo told reporters.

At least 139 former FARC rebels have been killed since the peace deal, under which some 13,000 members of the rebel group, including more than 6,000 combatants, demobilized.

The FARC has repeatedly raised concerns that members may be assassinated by right-wing gangs or drug traffickers, in an echo of thousands of targeted killings in the 1980s. (Reporting by Luis Jaime Acosta, Julia Symmes Cobb and Helen Murphy Editing by Jonathan Oatis and Phil Berlowitz)