Bulgaria's President Rumen Radev vowed Wednesday his country would implement "very strict measures" to curb football hooliganism, following racist behaviour from fans during Monday's international match against England.
He said it was "extremely displeasing" that Bulgaria - which he said saved 50,000 Jews from the Nazis during World War II - was being associated with racism.
"Our football is a mirror of our state," he said.
During the match, a European Championship qualifier, some Bulgarian fans made Nazi salutes and directed monkey noises at England's black players.
The game, which England won 6-0, was halted twice in an attempt to stop the abuse.
Afterwards, police arrested four football fans over the incident, and special forces raided the offices of the Bulgarian football federation.
The president of the association has resigned.