More than 700 people taken into pre-trial detention for "breaching the laws on mass gatherings," Interior Ministry says.
Hundreds of protesters have been jailed following the latest anti-government protests in Belarus, as anger mounts over the recent death of a protester.
The Belarusian Interior Ministry said on Monday that more than 700 people were taken into pre-trial detention for "breaching the laws on mass gatherings".
Thousands took to the streets of the Belarusian capital Minsk on Sunday, the latest of three months of demonstrations against the reelection of strongman leader Alexander Lukashenko in August.
Opponents of 66-year-old Lukashenko, who has been in power for more than two decades, say the election was rigged and insist political novice Svetlana Tikhanovskaya was the true winner of the polls.
The human rights group Viasna for its part reported that at least 1,200 people were detained on Sunday.
During Sunday's protests, armed police dispersed the crowds using tear gas and stun grenades and deployed water cannon.
Polish envoy summoned
Also on Monday, the Belarusian Foreign Ministry summoned the Polish envoy in Minsk and demanded that Warsaw extradite the founder of Nexta Live, the Poland-based opposition Telegram channel that has coordinated protests in the ex-Soviet country.
The ministry said that Warsaw should hand over to Belarus Nexta founder Stepan Putilo and Roman Protasevich, who was until recently Nexta editor-in-chief.
Earlier this month Belarus' Investigative Committee opened a criminal case against the pair and accused them of organising mass unrest following the August election.
Tikhanovskaya, who was granted shelter in EU member Lithuania shortly after the election, said on Monday she met with ambassadors of several Western countries to discuss further sanctions on Lukashenko's regime due to the "evident escalation of violence".
In a statement on Telegram, she added that new sanctions could be expected "this week."
The European Union has slapped sanctions on Lukashenko and his allies, citing election fraud and a violent crackdown on protesters.
EU in talks about new measures
Germany and the European Union are looking into ways to raise the pressure on the Belarusian leadership after hundreds of protesters were detained during mass demonstrations there on Sunday, a German Foreign Ministry spokesman said on Monday.
"The German government is in discussions with our EU partners about which additional restrictive measures might be suitable to further raise the pressure (on Belarus)," the spokesman said.
"It is conceivable that these measures could be directed against companies which are involved in human rights violations."
Several died in protests
Thousands took to the streets of Minsk last Friday to mourn the death of 31-year-old protester Roman Bondarenko who was pronounced dead a day after police arrested him.
Several people have died since protests erupted in August and the EU warned last week that Bondarenko's death could result in further sanctions.
A number of Western leaders have backed Tikhanovskaya and refused to recognise the results of the Belarus polls.
Moscow-backed Lukashenko has refused to step down and instead proposed reforms to the constitution.