Thousands of student-led protesters marched peacefully in Belgrade, demanding accountability for the deaths of 16 people in a station roof collapse and an attack on a student protest a year ago.
Thousands in city of Nis stood in silence for 15 minutes on Saturday, honoring railway disaster victims in a protest challenging the Serbian president's grip on power.
Thousands of students descended upon the Serbian city of Kragujevac on Saturday in the largest protest yet against the government over a deadly railway disaster in November.
Serbia wound up a rescue operation and opened an investigation on Saturday into a roof collapse that killed 14 and injured three at a railway station in the northern city of Novi Sad.
NATO official warned on Saturday that ethnic tension in north Kosovo could trigger a repeat of violence seen in the area last year, when four people died in a gun battle and NATO officials were hurt.
Serbia's government ministers on Friday agreed to reintroduce compulsory military service which was abolished 14 years ago as a step to improve the country's defence, said President Aleksandar Vucic.