People with flags and balloons walk toward  St. Basil's Cathedral on Red Square during a rally in Moscow on May 1. Russians celebrate the coming of spring and, since communist times, Labor Day on May 1. (Maxim Shemetov/Reuters) 

MOSCOW – The 1st of May in Russia is always a nationwide excuse for a party, but in this newly expansionist Russian epoch, Thursday’s rallies were far larger than usual.

Tens of thousands of jubilant Russians took to the streets of Moscow to march past the Kremlin, through Red Square and up a central boulevard – the first time that trade unions held May Day marches through Red Square since 1991, shortly before the breakup of the Soviet Union.

Children tugging on balloons, elderly, medal-bedecked veterans – and a wide range of Russians in between – sang old labor songs on a sunny Moscow day. Some sported signs saying “Let’s go vacation in Crimea,” the peninsula that was an autonomous region of Ukraine until it was annexed by Russia in March, setting off one of the most dangerous confrontations between Russia and the West since the end of the Cold War. Others carried banners condemning President Obama and NATO, which many Russians regard as a security threat that has crept up to their borders. In this flower-mad nation, many women carried red carnations.

Russian Communist Party activists parade in central Moscow on May 1, 2014, during their traditional May Day rally. (Kirill Kudryavtsev/AFP/Getty Images)

“Today is a wonderful day!” the head of the Moscow Trade Union Federation, Sergey Chernov, told the crowd from a stand in front of GUM, the famous department store that abuts Red Square. “Crimea and Sevastopol have returned to Russia! Unions have returned to Red Square!”

In keeping with the retro mood, President Vladimir Putin awarded five people the “Hero of Labor” medal, a Soviet-era honor that he revived last year. An oil company worker, a museum director, a farm manager, a high school teacher and the coach of the Russian National Synchronized Swimming team were all given medals Thursday.

“We have a very good tradition,” Putin said in a ceremony at the Kremlin. “On the 1st of May, the day of spring and Labor Day, we honor the citizens of Russia that, through their achievements, have improved the power, prestige and wealth of our country.”

But after the main rally had disbanded, a discordant tune sliced through the air. Seven protesters singing the Ukrainian national anthem and carrying a Ukrainian flag marched down empty, upscale Tverskaya Boulevard. More than a dozen police officers charged at them, throwing two men and one woman into a nearby police van and ripping up the Ukrainian flag. The woman shouted from the van that the police were being violent – but then the door slammed and her voice could no longer be heard.

“We're here because we have no alternatives. No one is listening to us,” said one protester who wasn’t arrested and who was dressed in Ukrainian yellow and blue. “There are very few of us,” she said.