Bulgarian police have made 70 arrests after violence flared in the capital Sofia before and after a meeting between the country's two best-supported clubs, Levski and CSKA.
Levski won the encounter 2-1 but police had to intervene after hooligans went on the rampage, damaging several buses and trams and throwing stones, injuring one young girl in the process.
Police made 20 arrests before the match and then some 40 more inside the ground as searches revealed some fans to be carrying knives and batons.
The interior ministry said a further dozen arrests came afterwards for hooligan behaviour on public transport.
Leader AaB slipped up in the Superliga title race as it lost 2-1 at home to Randers.