Tens of thousands of opposition supporters marched in the Belarusian capital of Minsk.
Tens of thousands of opposition supporters marched in the Belarusian capital of Minsk Sunday, defying a heavy security force presence that included water cannons and armoured vehicles.
The protest came a day after police officers detained hundreds of demonstrators at a women's march in the capital.
The opposition movement has kept up a wave of large-scale demonstrations every Sunday since President Alexander Lukashenko won a disputed victory in August 9 polls.
People holding red-and-white protest flags gathered at the "March of Justice" walked through central streets holding placards with slogans such as "Cowards beat up women" and "Get out!".
Natalya Chizhevich, a 60-year-old retired teacher said she came every week.
"Europe won't help us get rid of Lukashenko, the people themselves have to remove him," she said.
Several independent media outlets estimated numbers at tens of thousands, while Nasha Niva opposition newspaper put the figure much higher at 150,000. Previous marches have seen estimated turnouts of at least 100,000.
"I hope this won't die down. We come out every time, it's such a breath of fresh air," said another protester, 33-year-old Maxim Karpov.
"This all gives us strength to fight on."
Police and internal troops moved military trucks, water cannon and armoured personnel carriers into the city centre and set up barbed wire.
In the evening, large numbers of helmeted riot police with shields faced off against massed flag-waving protesters after detaining small numbers at the start.
The Viasna rights group said at least 30 had been detained in Minsk and 33 in other cities.
In the southwestern city of Brest, police said they used tear gas against protesters during tense street clashes and one officer fired a stun grenade into the air.
The government ordered a reduction in mobile internet coverage during the protests, while central Minsk metro stations were closed.
Opposition leader Svetlana Tikhanovskaya, who claimed victory over Lukashenko in the polls and has taken shelter in Lithuania, praised demonstrators for coming out "to bravely stand up for what they want."
The mass protest came after riot police cracked down Saturday on peaceful women demonstrators who wore shiny accessories for their so-called "Sparkly March."
They dragged protesters into vans, lifting some women off their feet to carry them.
Belarusian interior ministry spokeswoman Olga Chemodanova said Sunday that police had detained 415 people in Minsk and 15 in other cities for breaking rules on mass demonstrations. She said 385 had been released.
- 'Worth fighting for' -
The scale of Saturday's detentions prompted the opposition's Coordination Council to warn of a "new phase in the escalation of violence against peaceful protesters."
Among those detained was one of the most prominent faces of the protest movement, 73-year-old activist Nina Baginskaya, although she was later released.
The aggressive police tactics prompted an opposition Telegram channel, Nexta, which has more than two million subscribers, to publish what it said was a list of the names and ranks of more than 1,000 police.
Protesters have tried to pull off the masks and balaclavas of police who appear at demonstrations in plain clothes or in uniforms without insignia or name badges.
Opposition leader Tikhanovskaya on Saturday said Belarusians were ready to strip police obeying "criminal orders" of anonymity.
Lukashenko has dismissed opposition calls for his resignation and sought help from Russia's President Vladimir Putin, who has promised law enforcement backup if needed and a $1.5 billion loan.
Tikhanovskaya is to meet European Union foreign ministers Monday in Brussels as the EU prepares sanctions against those it blames for rigging the election and the regime's violent crackdown on protesters.
Authorities have jailed many of Tikhanovskaya's allies who formed the leadership of the Coordination Council, or driven them out of the country.
Campaign partner Maria Kolesnikova has been imprisoned and charged with undermining national security.
She released a message to protesters Sunday saying: "Freedom is worth fighting for. Don't be afraid to be free!".