Thousands of students took to the streets and boycotted the start of the school year in Belarus on Tuesday (1 September) and signs of a possible rift appeared in the opposition alliance.
Rallies against authoritarian President Alexander Lukashenko have persisted for weeks, since he claimed victory in an election last month that opponents said was rigged.
Lukashenko denies electoral fraud and shows no sign of backing down, despite Western powers threatening sanctions.
A senior U.S state department official said they were considering sanctions on seven individuals it believes were involved in falsifying the results of the election and violence against protesters.
Video showed students dragged away by masked security forces and police detained seven journalists covering the protests which the government said were document checks.
In a rare public reproach, Lukashenko's main challenger, Sviatlana Tsikhanouskaya, issued a statement criticizing the strategy of another opposition group with which she formed an alliance during the election campaign.
Tsikhanouskaya fled into exile in neighbouring Lithuania two days after the election and from there, she declared herself the rightful winner and launched an opposition council with the stated aim of ensuring a peaceful transfer of power.
Tsikhanouskaya said the council "should not be dominated by any political party", after opposition leader Maria Kolesnikova and her team announced the creation of a party called 'Together', and declared their aim; to enact constitutional reform.
But Tsikhanouskaya said this was a distraction from the goal of removing Lukashenko and holding new elections.
Later, Kolesnikova's camp said it did not wish to disrupt the council's work and backed Tsikhanouskaya's call for new elections.