People carry a cross during an anti-European Union march through the downtown attended by nationalist and catholic activists, in Warsaw, Poland, Saturday, May 7, 2016. (AP Photo/Alik Keplicz)

WARSAW, Poland - Tens of thousands of Poles — perhaps up to a quarter million — marched through Warsaw on Saturday to express their support for the European Union and opposition to a conservative new government which they accuse of eroding democracy.

City authorities estimated that 240,000 turned out in one of the largest street demonstrations this Central European country has seen since communism collapsed 27 year ago. Police said there were 45,000 at the event's peak, but that the number did not include those who came and left at other points.

Either way, an Associated Press reporter saw an endless flow streaming down main streets in what clearly was the largest anti-government demonstration since the Law and Justice party took all power last year and embarked on deep restructuring that it has dubbed "good change."

The protesters object to centralization of power under the right-wing party. The greatest controversy surrounds steps that have paralyzed the constitutional Tribunal, a top court, neutralizing it as a check on the party's power.

Law and Justice maintains that it has a democratic mandate to make the changes after decisive electoral wins last year.

"I am marching because I don't like the 'good change' and I don't like this dividing of Poland and I don't like the weakening of Poland's international position," said Lukasz Lomanowski, a 29-year-old horse-riding instructor.

His voice could be hardly heard amid the sound of trumpets and chants of "we say 'no thanks' to the rotten change" and "free judge, free Poland," raised by the crowd waving white-and-red national flags and the blue-and-yellow EU flags.

One leader of the pro-EU march, Civic Platform party leader Grzegorz Schetyna, a former foreign minister, declared it the biggest demonstration in the democratic era. It was not immediately clear, though, how the numbers compared to protests by miners in the 1990s during the transition to a market economy.

"We will not allow for the nightmare of authoritarian rule to happen," Schetyna said.

There was a counter-protest by about 1,000 nationalists and Catholic groups who voiced their opposition to the influence of Brussels on Poland's affairs and the secular lifestyle that has come with EU membership. They held up crosses and an image of St. Mary, praying and singing hymns.

The demonstrations highlight a bitter divide in Poland between those who want deeper integration with Europe and those who feel that EU membership has eroded national sovereignty, only recently regained after the end of the Cold War.

Ruling party leader Jaroslaw Kaczynski said the demonstration was an expression of dissatisfaction by some groups with the fact that his party won the elections, and was "not a big problem." Poland wants to participate in reforming the EU, but wants to be "separate" on social values, he said.

The protest was organized jointly by the opposition centrist Civic Platform party, which lost power last year, by the civic movement Committee for the Defence of Democracy, known as KOD, and by other opposition parties.

KOD was created in November, shortly after Law and Justice took power and began taking steps that have weakened the constitutional Tribunal. That move and others which have helped the party centralize power have been condemned by the EU and the Council of Europe, a human rights group.

The ruling party says its changes are aimed at building a stronger nation free of what it says is the continued influence of former communists. Some 5.7 million voted for the party in this nation of 38 million in October elections and it remains popular.

News from © The Associated Press, 2016