More than 200 protesters gathered on Saturday in New York's Zuccotti Park to mark the six-month anniversary of the Occupy Wall Street movement and clashed with police, resulting in several arrests and three officers injured, officials said.
At least four people were arrested, according to organizers.
Police would not confirm the arrests but said three officers suffered injuries. Police did not provide any details as to the extent of the injuries.
Organizers vowed that Saturday's rally was the first of several events planned to protest economic injustice.
Critics say the Occupy movement lacks demands and direction and has lost momentum.
Protester Paul Sylvester, 24, of Massachusetts said he was "thrilled" to be back at the park but said he hoped the movement would begin to crystallize around specific goals.
"We need to be more concrete and specific," he said.
Inspired by the pro-democracy Arab Spring, protests at Zuccotti Park near Wall Street, where demonstrators set up camp in September, sparked a wave of protests in towns and cities nationwide.
At the park on Saturday, street theater troupes performed and guitar players led sing-alongs.
Some boisterous protesters marched through the streets of New York's financial district, chanting "bankers are gangsters" and cursing at police.
As they have in past marches, protesters led police on a series of cat-and-mouse chases. Marchers at the front of the crowd would suddenly turn down narrow side streets, startling tourists and forcing police to send officers on motor scooters to contain the crowd.
The movement has made headlines for its clashes with police, but it has struggled to grow beyond the initial protest camps that sustained it.
Its future has come into question as well due to a lack of funds. A spokeswoman from the movement's accounting group said it has about $20,000 for items such as transit fare, food and materials and another $89,000 for bail money.
Liesbeth Rapp, 27, who was performing street theater about economic injustice, said protesters are ready to make some changes. "I think we've learned a lot about being strategically and tactically smarter," she said. "We're learning to decentralize, and to work in smaller groups."
Still many protesters found themselves arguing with one another over their political views. One man wearing a large white Native American head dress exchanged harsh words with a woman who said she found it offensive.
"Symbols have meaning," she said, adding that she has Native American friends who would be offended by his outfit.
"And I have friends who would be offended by your taking offense," replied the man in the head dress.
Protesters camped in Zuccotti Park last fall were evicted after two months.
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