Thousands turned out in central Prague on Sunday to protest against recently extended restrictions designed to contain the coronavirus.
Footage of the demonstration in Prague showed many protesters not wearing masks and standing close to one other.
A day earlier in Denmark, protesters became violent and lit fireworks as police arrested nine people in the capital Copenhagen and northern city Aarhus.
The demonstrators, who call themselves 'Men in Black', gathered at the town hall square in Copenhagen and clashed with police in the wintry conditions.
Denmark and Czech Republic are among the nations to extend lockdown measures in the fight against soaring Covid-19 infections and a new, more infectious variant.
Denmark on Tuesday reduced gatherings to five people and made travel more difficult, stopping entry from foreigners without a negative test and proper purpose.
But the rules in Copenhagen are still not as strict as the lockdown measures taken in Melbourne at the height of Australia's pandemic, which included a curfew.
The protests follow similar rallies in the UK last week.
Police in central London made some 21 arrests on Wednesday days after England was placed in a new national lockdown over rising COVID-19 cases.
On Sunday, medical professionals in the UK warned of an imminent collapse in the healthcare system amid rapidly rising infection rates linked to gatherings over the holiday season.
Meanwhile in Germany's Munich, the lure of fresh snow and sunshine brought people flocking outside, despite the restrictions.
Police in Munich cleared crowds on Sunday at the city's Nymphenburg canal, which froze over with a thin layer of ice.
They called on residents to avoid the site near the Nymphenburg Palace, as there were already too many skaters and curling fans who failed to follow social distancing guidelines.
German chancellor Angela Merkel said her country was entering the toughest phase of the pandemic as she called for restrictions to be better applied.
Experts in Italy are also calling for tougher restrictions to be implemented despite good vaccine progress being made.
- with Reuters, EFE