The Belarusian Interior Ministry refused to give comments on Sunday on the alleged detention of opposition supporters in Belarus on election day.
Belarus is holding presidential elections on December 19. A total of 10 candidates are running for presidency. Incumbent President Alexander Lukashenko is set to secure a landslide victory and claim a fourth term, according to exit polls.
"We give no comments on this issue," Interior Ministry spokesman Viktor Novikov said.
Vladimir Neklyaev, 64, member of the Govori Pravdu (Tell the Truth) civil movement, who gained just 4.49% of the vote said police held his election agent Mikhail Pashkevich on Sunday and the leader of a youth organization Molodoi Front (Young Front), Dmitry Dashkevich, on Saturday evening.
Other candidates also said several their supporters were detained.
Shortly after elections, Neklyaev refused to cast his ballot in the ballot box and took it with him writing on it "New election without Lukashenko."
The opposition said it already had evidence of vote-rigging and called on its supporters to meet at October Square in Minsk after the polls were over and to demand holding new elections.
The Belarusian Interior Ministry and State Security Agency promised to "suppress adequately and decisively any illegal actions posing a threat to life and health of citizens."
The head of the Belarusian presidential administration, Vladimir Makei, confirmed information of planned riots organized by the opposition. "We know that they do not intend to hold this event peacefully."
He said opposition prepared "groups of gunmen, fireworks and even explosives."