Occupy Wall Street protesters march near Wall St.

NEW YORK (AP) — Occupy Wall Street protesters have been marching in small groups around Manhattan's financial district to mark the anniversary of the grass-roots movement.

About a dozen were arrested Monday after sitting on the sidewalk.

Loud chanting and the sound of drums filled the air. The demonstrators clogged traffic. Dozens of police officers and vans lined the streets.

But the protests lacked the heft of last year's Occupy events. Last year there were thousands of protesters. On Monday morning, there were a few hundred at most.

Earlier, they gathered across from Zuccotti Park, the site of the movement's birth.

Events are planned in more than 30 cities worldwide.

In San Francisco, they include an afternoon march to the Financial District and an evening rally outside Bank of America.