Earlier today, the electoral commission officially registered Milinkevich, along with President Alyaksandr Lukashenka, Liberal Democratic Party leader Syarhey Haydukevich, and Social Democratic Party leader Alyaksandr Kazulin for the 19 March poll.
AFP says the Milinkevich supporters were arrested on various pretexts, such as the state of their vehicles or problems with their identity papers.
Lukashenka is seeking a third term in office and is seen as the heavy favorite.
The European Union and United States have voiced concern over whether the vote will be free and fair.
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