Hundreds of marchers took to the streets in Poland’s capital, Warsaw, on Sunday to protest the alleged democratic backsliding created by the country’s ruling party. 

The march was led by the opposition Civic Platform party, which has heavily criticized Polish Prime Minister Mateusz Morawiecki’s ruling Law and Justice party. The total number of protesters was unclear, but Warsaw Mayor Rafal Trzaskowski, a member of the Civic Platform party, estimated there were at least 500,000 people, per The Associated Press, though Polish media had estimated only 300,000. 

The massive crowds marched alongside Trzaskowski, as well as the leader of the Civic Platform, former Prime Minister Donald Tusk. Also marching was former Polish President Lech Walesa, who received a Nobel Peace Prize for helping end Communist rule in Poland in 1989. The crowds reportedly chanted “Democracy!” and “Constitution!” and gathered in front of the prime minister’s office, as well as the seat of Polish President Andrzej Duda.

Protests have been ongoing in Poland over the actions of the Law and Justice party, with Polish citizens telling the AP they fear their country, long a bastion of democracy, is following Hungary and Turkey down an autocratic path. Law and Justice party leaders have been accused of constitutional violations, erosion of state media, and other violations of freedoms. 

Morawiecki and his government have denied that Poland is backsliding democratically, with the prime minister saying he wants to “protect traditional Christian values against liberal pressures from the West,” according to Reuters. 

The Civic Platform party will try to unseat the Law and Justice party from power in a national parliamentary election later this year. A Politico poll from May 31 shows Law and Justice leading Civic Platform 35% to 28%. However, the outlet noted that Law and Justice doesn’t have enough current support to guarantee a parliamentary majority.