Authorities reported on Friday that a total of 33 police officers and 24 football fans sustained injuries during clashes on the sidelines of the Euro 2024 qualifier between Bulgaria and Hungary, which concluded in a 2-2 draw.

"Twenty-four injured were examined, including seven who were hospitalized with head traumas, broken legs and arms, and many who were gassed with pepper spray," Katya Sungarska, emergency center spokeswoman, told Agence France-Presse (AFP) early Friday.

"The injured police are 33; there are some with serious injuries and hospitalized," Stefan Ivanov, deputy chief of the Sofia police directorate, said at a briefing.

Some 33 football fans were detained last night, and arrests continue, he said, slamming the violence as "an unprecedented violation of public order with serious aggression and posing a high risk."

UEFA ordered the game to be played behind closed doors after a request by the national federation, which feared potential trouble following the fans' call for a major protest against the Bulgarian Football Union (BFU).

Police said early Friday that the protest outside the national stadium in Sofia gathered over 4,000 supporters.

They shouted "Resign!" and held banners saying "18 years is enough" to call for the resignation of longtime BFU president Borislav Mihaylov.

Violent clashes erupted after fans started to throw smoke bombs, pavement blocks, stones and beer bottles at police lines.

Over 1,500 police officers in full anti-riot gear were in place to ensure security.

Two water cannons were deployed to disperse the crowd – a measure put in place relatively rarely in the Balkan country.

An AFP reporter saw at least seven fans with various head injuries after police pushed away the supporters, who set fire to a police minivan and several garbage containers.

Fans' anger has built up in recent years over the poor results of the national team that has failed to qualify for any major tournaments and went through numerous coaches during Mihaylov's time at the helm of the federation.

The controversial president quit in 2019, but then withdrew his resignation and was reelected in 2021, despite a record marred by suspicions of match-fixing and a racist abuse scandal during a match against England in 2019.

Despite the point earned in Thursday's draw, Bulgaria are last in their Euro 2024 qualifying group, with three points from seven games.

Hungary qualified for the finals as a result of the draw.