Extradition and European Arrest Warrant Act
Chapter three - EXTRADITION PROCEDURE
Title I - Extradition at the request of another state
Article 14
(4) Within the period under para 2 the District Prosecutor shall:
1. Provide the requested person with a defence counsel, where the latter has none, and an interpreter if he/she has no command of the Bulgarian language;
Language
Rights during investigation - access to interpreter and translation if questioned in other language
Rights during investigation - legal assistance
EDIT.