Police in Croatia have arrested dozens of football fans after fights broke out following a UEFA Nations League match between Croatia and Poland. The country"s interior ministry said on Monday that Polish fans attacked Croatian supporters and then took aim at police in the eastern town of Osijek. Another clash took place later on elsewhere, the ministry said without specifying where. "Dozens of people have been detained and a criminal investigation is under way," the ministry said on social media. The authorities did not say exactly how many Polish nationals had been arrested. The fights happened following Croatia"s 1-0 victory against Poland, with the two now equal on points in League A Group 1. At least five fans were also detained in Osijek before the Group A1 match for fighting in which a Polish national was injured. Some Croatian fans were left enraged after hearing the Polish anthem right before kickoff, mistaking it for the former Yugoslav one due to their close resemblance, domestic media reported. Croatia declared independence from Yugoslavia in 1991, sparking a four-year war which was a part of the bloody dissolution of the former socialist republic. The ministry added that two people had been arrested for using pyrotechnics. — Euronews