WARSAW, Poland (AP) — Opposition politicians in Poland criticized police Saturday for detaining anti-fascist activists but not reacting to the appearance of a Nazi-era symbol during a nationalist march.

The detention of the activists occurred during Friday's yearly far-right-led Independence March in Warsaw.

Many liberal groups who oppose the march have accused the police for years of displaying favorable treatment toward the nationalists while treating protesters of the event unfairly.

The counter-protesters held white roses and a banner reading “Nationalism is not patriotism” before police removed them from a location near the march route.

An opposition lawmaker, Michal Szczerba of the centrist Civic Platform party, accused the ruling Law and Justice party Saturday of creating “an oppressive state” with its treatment of peaceful protesters.

A Polish senator who also is a member of the political opposition, Krzysztof Brejza, tweeted a photo from the march of participants carrying a banner with the “Black Sun” symbol of Nazi Germany's SS guards. Brejza noted that police did not intervene.

The promotion of totalitarian ideologies is illegal in Poland.

“During the Warsaw Uprising in 1944, thousands of Poles died at the hands of German Nazis from the SS. I don’t know why the police didn’t respond to such criminal symbolism in Warsaw, which suffered so much in World War II. On the other hand, demonstrators with democratic views were forcibly removed,” Brezja told The Associated Press.

A police spokesman, Sylwester Marczak, said the detained activists, some from the group Obywatele RP, which means Citizens of Poland, were held for several hours because they had restricted the work of the police, and refused to show their identification documents.

“These are grounds for detention,” Marczak told TVN24, an independent all-news broadcaster in Poland.

Hanna Machinska, the country’s deputy human rights commissioner, went to the scene Friday evening to intervene. She said the protesters did not provide their IDs because they were not given a legal reason for doing so.

Machinska told TVN24 the protesters were standing on a lawn and not disturbing the march or its participants. She said those detained included older adults and her first mission was ensuring they had the chance to use a toilet.