Four men have been detained by Bulgarian police in relation to the racist abuse of England players on Monday night.
The Bulgarian ministry of the interior told the PA news agency that the operation to identify individuals involved in the abusive chanting was still ongoing.
England’s black players were targeted throughout the match, and the Bulgarian Football Union has been charged by UEFA over the racist behaviour of its fans.
A spokeswoman for the ministry said: “The operation of Sofia metropolitan police is still ongoing. At this stage four males are detained.
“The work is ongoing to establish whether they were involved in this incident. The operation continues during the day.”
The spokeswoman also confirmed that special forces from the ministry’s general directorate for combating organised crime had raided the BFU offices on Tuesday.
The BFU’s president, former national team goalkeeper Borislav Mihaylov, announced his resignation in the wake of Monday night’s racist chanting.
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