Opposition organisations in Belarus said on Tuesday police had raided their offices in the capital Minsk and other cities and arrested staff.
"The police came and arrested everyone who was there, around 20 people," activist Sergei Voznyak, from opposition group "Speak the Truth", told Reuters.
Other organisations said police seized computers, flash cards and discs from their offices and raided the flats of independent journalists during raids in Minsk, Brest and Grodno.
An Interior Ministry spokesman declined to comment.
The European Union and United States have long shunned Belarussian President Alexander Lukashenko, accusing him of maintaining power through unfair elections and the suppression of dissent.
Masked police in March seized computers from the offices of an opposition website and an independent newspaper, drawing criticism from international rights groups and opposition politicians.
Belarus sentenced an opposition activist in early May to a lengthy jail term for the first time since an amnesty for political prisoners two years ago raised the prospect of improved ties with the West.
ReutersLast Mod: 18 Mayıs 2010, 22:49