Karin Limdal, the spokeswoman for the 2,000-strong EU police mission said the policeman was shot in the leg but was out of danger.
She said special police units were called in to support local forces in separating the two sides that pelted each other with stones at the foot of the bridge that splits the city into two halves. Machine gun fire and explosions were also reported.
The clashes – sparked after Turkey defeated Serbia in the semi-finals of the basketball world championship – highlighted the deep ethnic divide that runs between the two ethnic foes over a decade since the end of the Kosovo war in 1999.
The clashes started when Albanians, in the southern part of the ethnically divided city "started celebrating Turkey's victory," said police spokesman Besim Hoti said. Doctors in the Serb-run north said a Serb youth was shot and wounded.
Mitrovica was divided 11 years ago.