KYIV, Ukraine (AP) — Protesters calling for the resignation of Belarus’ authoritarian president marched in small groups Thursday throughout the capital of Minsk, the first sizable turnout of demonstrators since weeks of protest rocked the country last year.The groups marched through courtyards and streets in a tactic aimed at avoiding widescale arrests like those during the massive protest gatherings of 2020, some of which approached 200,000 people.Riot police set up a heavy presence in the center of Minsk on Thursday and deployed water cannon. Videos on social media showed police arresting people holding the red-and-white flags that are an emblem of the opposition to President Alexander Lukashenko.The Viasna human rights organization said at least 52 people were detained by police.Lukashenko, frequently characterized as Europe’s last dictator, has strongly repressed opposition and independent news media during 26 years as president.The protests that broke out in August after a disputed election which gave him a sixth term in office were the largest and most persistent show of opposition the former Soviet republic has seen.Protests dwindled markedly in recent months as freezing winter weather gripped the country and opposition morale flagged amid harsh arrests.More than 33,000 people were arrested during last year’s protests, many of them beaten by police. Some of those arrested have drawn long prison sentences, including two journalists who were sentenced in February to two years in prison for covering the protests.But opposition leader Sviatlana Tsikhanouskaya, who ran against Lukashenko and then fled into exile in Lithuania after the election, has called on Belarusians to start a new wave of protests.The Thursday protest marked the anniversary of the 1918 declaration of the Belarus People’s Republic, an independent state that lasted only a few months before the Red Army moved in. The opposition traditionally observes the anniversary as the country’s unofficial Freedom Day.Story continuesThe U.S. Embassy on Thursday called on Belarusian authorities to stop their repression, saying that “The United States congratulates the people of Belarus on the March 25 anniversary and looks forward to the day when the people of Belarus will define their own future.”Also Thursday, police arrested several top figures of an organization of ethnic Poles in Belarus. The arrests came a day after their leader, Andżelika Borys, was sentenced to 15 days in jail for holding unauthorized mass events.Authorities on Thursday opened a criminal case against Borys for allegedly inciting social hatred, a charge that could carry a sentence of 12 years. Leaders of the ethnic Poles have organized actions in memory of the anti-communist underground in Poland and Belarus after World War II that have offended Belarusian authorities.