Hundreds of protesters marked May Day on Tuesday with demonstrations, marches and rallies, marking the spring revival of the Occupy Wall Street movement.
Police had arrested dozens by Tuesday night.
At one point, people spilled out onto Fifth Avenue in a confrontation with police. Marchers briefly flooded the avenue and blocked traffic before police in riot gear pushed the crowd back onto the sidewalks. The group chanted: ``We are the people. We are united!''
Earlier in the day, activists spread out over the city with Occupy members leading a charge against financial institutions. They faced police lined up in front of Bank of America on West 42nd Street and chanted: "Bank of America, bad for America!''
Julian Kliner, 22, said protesters' main issue with the banking giant is "how many people the Bank of America foreclosed as a result of predatory lending.''
Organizers initially called for protesters to block one or more bridges or tunnels, but some protesters said later in the day those plans had been canceled. Occupy activists also had said they planned to bring business to a standstill on May Day. But there was no sign of any major business disruptions.
In the afternoon, several thousand people converged on Union Square with signs, bullhorns and other paraphernalia. Some chanted at passers-by, while others relaxed on picnic blankets in the sun. Through loudspeakers, protest organizers called for an end to corporate greed, housing foreclosures, and war.
The May Day gatherings included nostalgia among those who participated in the Occupy protests last fall. Many at Bryant Park hugged each other, recognizing faces they knew from Occupy's now-dismantled headquarters in Zuccotti Park.
Occupy organizer Mark Bray said the mood had changed since the group's first organized events late last year.
"There was a sense of novelty to Occupy in October,'' said Bray, 29, a Ph.D. history student at Rutgers University. "Today is more celebratory, and nostalgic.''
With Zuccotti Park now empty of encamped protesters, "people still feel the need for that kind of space,'' he said. "I think the Zuccotti experience touched people _ the experience of being there and having a cultural and political outlet.''
But 22-year-old Sophia Clark said she believed the loss of Occupy's encampment had ultimately strengthened the movement.
"It just underscores the way people are not being heard,'' said the Sarah Lawrence College student. "Taking away Zuccotti Park was just underscoring how the system doesn't work.''
The city broke the Zuccotti camp up in November, citing sanitary and other concerns, but the movement has held smaller events and protests periodically since then, with many members promising a warm-weather resurgence. Tuesday morning, nearby Wall Street was heavily barricaded as office workers streamed by on their way to work.
About 300 teachers and students skipped high school and college classes to hold activist teach-ins in Manhattan's Madison Square Park, Bray said. Earlier, more than 100 protesters walked over the Williamsburg Bridge and filed into a park on the Lower East Side.
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