The country's recent election sparked unprecedented protests against the government, which is accused of rigging the vote in its favour.
ADVERTISEMENTActivists and opposition parties marched in Belgrade on Tuesday night calling for around 30 students detained while protesting at the weekend to be freed from custody.
The protest is the ninth since December's general election, which is widely alleged to have been illegally manipulated in the government's favour.
Sunday's protest, where the students were detained, was the first to turn violent since the protests started. The protest also saw eight police officers were injured, according to the head of the Interior Ministry's Police department, Ivica Ivkovic.
"Those arrested are suspected of attempting to violently change the constitutional order, and of violent behaviour at a public meeting according to the Criminal Code of the Republic of Serbia," said Ivkovic, adding that the number of arrests was likely to rise.
On Tuesday night, people gathered in front of the headquarters of the Republic Electoral Commission (REC) in Belgrade. Serbia Against Violence, an opposition coalition of political parties, is demanding that the elections be annulled.
The election saw President Aleksandar Vučić's Serbian Progressive Party return to power with a majority in parliament.
However, domestic and international observers have reported "irregularities", claiming ballot box stuffing and vote buying.
In an emergency address to the nation on Sunday evening, Vučić blamed the unrest on foreign interference, and has dismissed claims of fraud.
The electoral commission announced on Wednesday that the election would be re-run in just 30 polling stations out of 8,000 nationwide.
Germany on Monday condemned the reported election irregularities as “unacceptable” in a European Union membership candidate country.