According to information to Reuters, security forces are said to have run towards a tent near the parliament, which was set up by supporters of the country's president Aleksandar Vucic. Shortly afterwards, shots were heard and a fire broke out in the tent.
The temporary camp has blocked roads outside the parliament and a nearby park for months. The cause of the fire was not immediately known.
It is also unclear who fired the shots.
According to the state television channel RTS, one person has been arrested and another has been taken to hospital, but the police have not confirmed any details.
