NEW YORK - Dozens of arrests were reported on Monday, the first anniversary of the Occupy Wall Street movement, as protesters converged near the New York Stock Exchange (NYSE) and tried to block access to the exchange.The protests attracted about a thousand activists, less than last fall’s numbers, highlighting the challenge the movement has faced in trying to sustain momentum after sparking a national conversation about economic inequality last fall.The New York Police Department, which set up a broad perimeter to block access to the NYSE by anyone other than exchange workers, said it has made “multiple arrests” by midmorning. Police were also posted at major banks and government buildings, and guarded Wall Street’ landmark Charging Bull, a 7,100 pound bronze sculpture.At least 70 demonstrators marking the one-year anniversary of the movement, witnesses said.Some were arrested when they started moving from Zuccotti Park, the birthplace of the Occupy movement, toward Wall Street as police on horseback blocked side streets. Others were seen being arrested by police at another approach to Wall Street.Policemen and protesters squared off at various points on the blocks near the Stock Exchange. At various points protesters tried to block sidewalks leading to the Stock Exchange, but were dispersed by the police. Police had set up barricades on several streets leading to the exchange and were asking identification from workers seeking to gain access.In one confrontation, several hundred people marched slowly along Broadway, a famed avenue, and as part of the group passed Wall Street, a line of officers separated the march into two parts. A few moments later, police officers approached a man who had been loudly yelling objections to the metal police barricades that cordoned off Wall Street. The officers grabbed the man, who began shouting “I did nothing wrong,” then removed him. As they were leading him away, a line of officers pushed a large crowd of people, including news photographers, away from the arrest.Police vans were parked on side streets throughout the financial district and helicopters buzzed overhead. Men in suits walking to work passed contingents of officers posted on corners.One early gathering spot on Monday was the Vietnam Veterans memorial on Water Street where about 400 protesters assembled. About 200 people had gathered at Zuccotti Park, which protesters took over last year and used as an encampment.Protesters had planned to converge from several directions and form a “human wall” around the stock exchange to protest what they said was an unfair economic system that benefited the rich and corporations at the expense of ordinary citizens.