Three editors of major Belarus independent media platforms were detained in Minsk on Saturday, their outlets said, along with dozens of others, at the site where fresh protests were due to begin against the rule of President Alexander Lukashenko.
The city square where the demonstration was called to start on Saturday afternoon was surrounded by police vehicles and prison vans, and roads leading to it were closed, as several small groups of people gathered at its edges.
Police detained a few dozen people at this site, videos shared on Belarus opposition media channels showed, with scenes of black-clad officers violently detaining people, including what appeared to be passersby.
Among the detained were Galina Ulasik and Anna Kaltygina, editors at opposition outlet TUT.by, the outlet, whose channel on the Telegram messenger app is followed by over 400,000 people, said.
Another outlet, Nasha Niva, with 90,000 Telegram readers, said its editor-in-chief Yahor Martsinovich was also detained at the square, along with a photographer.
The platform, which regularly shares videos of detentions and police brutality filmed by its followers, is a significant source of information on anti-government protests in Belarus.
The demonstrations became a weekly fixture in the capital and beyond after an election in August returned Lukashenko to power that opposition figures deemed rigged.
After a two-month lull, opposition leaders have called on the public to ramp up protests once again.
Belarus authorities warned early on Saturday that anyone participating in these actions was liable to criminal prosecution.
The Minsk Investigative Committee said it had opened a case against the authors of posts on the Telegram messenger app that called for people to go out on the streets.
Dozens were detained on Thursday during a relatively minor protest, coordinated to coincide with 'Freedom Day', an unofficial anniversary marking Belarus' 1918 declaration of independence from Russia, a period that proved short-lived.
Over 34,000 people have been detained since the start of regular demonstrations in August last year, which attracted hundreds of thousands of people and formed the biggest challenge so far to Lukashenko's nearly 27-year-rule.
Lukashenko denies electoral fraud and has accused the West of sponsoring the protests.
On Friday, Belarus was disqualified from the Eurovision Song Contest after lyrics of submitted songs were deemed to be mocking of anti-government protests.