Video clips show how the government supporters are throwing distress rockets, stones and bottles at the demonstrators, who in turn are throwing back various objects.
During the continued protests on Wednesday, another police officer was injured in addition to the 16 who were affected the day before. A total of at least ten people are reported to be injured.
Thousands of demonstrators have gathered in several places around the country. Tear gas has been used to disperse the crowds and several people have been arrested while riot police have been deployed.
The protests, mainly against Serbia's president Aleksandar Vucic, have been going on for more than nine months. The starting point was an accident at the train station in the city of Novi Sad, when the station's roof collapsed, resulting in 16 people being killed. The demonstrators see the accident as a result of corruption in the government and have since then demanded Vucic's resignation.
