Extradition and European Arrest Warrant ACT
Chapter two - CONDITIONS FOR EXTRADITION. GROUNDS FOR REFUSAL OF EXTRADITION
Article 6 - (1) The extradition of the following persons shall not be granted:
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3. Foreign nationals enjoying immunity from the criminal jurisdiction of the Republic of Bulgaria;
Immunity
Obligations towards the sending State
State privileges and immunities
Obligations arising out of State or diplomatic immunity
EDIT.