Protesters marched to the Belarusian government building in Minsk on Friday (August 14) after widespread claims that prisoners freed on Friday after days of detention had been tortured in prison.
Hundreds have been released from jail after being interned during the violent state crackdown on demonstrations against President Alexander Lukashenko's controversial re-election last Sunday.
Opposition leader Sviatlana Tsikhanouskaya has accused the authorities of creating a "bloodbath" and has called for more rallies this weekend.
The Belarusian government announced on Thursday night that 1,000 people arrested during the protests were being let go.
However, many people were still waiting for news of missing friends and relatives on Friday morning.
Testimony describing serious human rights abuses by police and prison guards is growing.
Amnesty International says there is mounting evidence of the widespread torture of peaceful protesters.
