Border Police said they detained four Bulgarians on 3 November on suspicion of illegally taking foreigners across the border. The operation took place in Burgas, Smolyan, Ruse and Dragoman. It is the third organised people-smuggling group broken up in Bulgaria in 10 days.
The youngest of the four is 18 and the oldest is 47. The other two are 21 and 25. All have been charged, and the supervising prosecutor ordered them held for up to 72 hours.
Police searched 7 addresses in all and seized items linked to the criminal activity.
Border Police said the foreigners, mostly from Iran, Iraq and Syria, crossed the borders with Greece and Turkey. They were then driven by car to the interior of Bulgaria and taken on towards Romania.
The investigation began in February this year. The pre-trial case is being run in Momchilgrad, under the supervision of the district prosecutor's office in Kardzhali.