Tens of thousands of people have rallied in the Belarusian capital Minsk for a new protest against the president.
Riot police, backed by water cannon and barriers, sealed off parts of the city and a number of arrests were made, with reports of injuries.
Protesters seek the resignation of President Alexander Lukashenko.
They accuse the authorities of rigging his re-election just over a month ago, sparking deadly mass unrest.
At least four people have died and hundreds have been injured since then, as the government tried to stamp out dissent.
A number of opposition figures have fled the country, On Saturday, activist Olga Kovalkova became the latest to say she had taken refuge in neighbouring Poland amid threats of imprisonment.