Bulgarian authorities have detained two men - one from Syria and one from Afghanistan – considered to be a threat to national security, the Interior Ministry said on Wednesday.

The two men were detained in two separate operations in Sofia conducted jointly by the the Interior Ministry Migration Directorate and the State Agency for National Security DANS.

The arrests were made on Wednesday. The names of those detained were not disclosed.

DANS has moved to expel the two men and ban them from entering Bulgaria for five years.

The Syrian citizen, permanently residing in Bulgaria for the past 30 years, had left for Syria after the start of the conflict there. He was found to have been “in contact with various Syrian armed groups, including terrorist organizations from the end of 2013 until the middle of 2014”, the Interior Ministry said in a statement. He returned to Bulgaria in the middle of last year but has regularly travelled to Turkey and Syria since then.

His arrest was a follow-up to an operation conducted by DANS on 1 July 2015 to crack down on a ring for trafficking of illegal migrants from the Middle East to Bulgaria and western Europe.

Bulgarian authorities have found that the Syrian citizen is one of the organizers of the human trafficking ring. During the operation on 1 July he was in Turkey. He was arrested upon return to Bulgaria two weeks later.  

The second detainee is an Afghan national who illegally entered Bulgaria from Turkey at the beginning of the year.

The Bulgarian authorities have found that his behaviour "matched the risk profile of a person belonging to terrorist groups and professing radical ideology”. Data collected in the course of the investigation justified a conclusion that the Afghan citizen sympathized with the goals of Taliban movement, took part in armed clashes in Afghanistan and “was probably connected with the terrorist organization," according to the statement.