Police arrested protesters during the Occupy Wall Street march. (Anjali Mullany/News)

Thousands of Occupy Wall Street protesters swarmed the Brooklyn Bridge Saturday, shutting down car lanes and setting up yet another tense showdown with the NYPD.

Roughly 500 people were arrested after standing in the roadway, blocking the Brooklyn-bound lanes. Traffic in the opposite direction was slowed — but still running after the 4 p.m. standoff.

An army of cops swooped in after the demonstrators took over the bridge’s pedestrian walkway and flooded onto the car lanes heading to Brooklyn. The showdown halted traffic on the bridge for nearly three hours.

While some of the protesters claimed cops set a trap for them, NYPD spokesman Paul Browne insisted the arrests came after the demonstrators were warned multiple times to stay off the roadway.

“Some complied and took the walkway without being arrested,” Browne said. “Others proceeded on the Brooklyn-bound vehicular roadway. The latter were arrested.”

The march started from Zuccotti Park, the homebase for the two-week old protest against corporate excess.
When demonstrators reached the base of the span, a bottleneck formed and many started marching up the pedestrian walkway.

Others walked straight onto the roadway, and several climbed down from the walkway moments later to join them.

“We were supposed to go up the pedestrian roadway,” said Robert Cammiso, a 48-year-old student from Brooklyn.

“There was a huge funnel, a bottleneck, and we couldn’t fit. People jumped from the walkway onto the roadway. We thought the roadway was open to us.”

After allowing some of the protesters to cross, officers trapped some 400 on the bridge using orange nets and vehicles – and started slapping cuffs on them.

Police called in NYPD and MTA buses to haul away the handcuffed demonstrators.

Some of the protestors managed to elude arrest by climbing from the roadway to the pedestrian walkway.

“[The cops] were respectful,” Cammiso said. “They were as good as they can be. They were doing their job.”

Not everyone agreed with that assessment. Etan Ben-Ami, 54, said it seemed the NYPD laid a trap for the protesters.

“It seemed as if they deliberately moved back to allow people onto the roadway,” said Ben-Ami, a psychotherapist from Brooklyn.

By 5 p.m., protesters clogged both the walkway and Brooklyn-bound car lanes. Just after 6 p.m., some of the protesters moved to the Manhattan Bridge.

At one point, about another 100 protesters marched from Zuccotti Park and gathered outside City Hall with 200 others who had scampered off the bridge. The mass of protesters faced down a wall of cops blocking the bridge, chanting,

“Whose streets? Our streets” and “Let them go.”

The arrests marked the second Saturday in a row protesters landed in cuffs.

Last week, cops arrested more than 80 people near Union Square. During that roundup, Deputy Inspector Anthony Bologna doused a handful of women with pepper spray – spawning a video clip that helped embolden the movement.

NYPD Internal Affairs and the Civilian Complaint Review Board are probing the incident.

Police arrested protesters during the Occupy Wall Street march. (Anjali Mullany/News)