OAKLAND, California - Police in riot gear clashed with protesters in Oakland in the early morning hours on Thursday, firing tear gas to disperse demonstrators lingering in the streets after a day of mostly peaceful rallies against economic inequality and police brutality.

The confrontation, which erupted after midnight, appeared aimed at preventing the protesters from expanding their foothold in the streets around a public plaza that has become a hub for demonstrations in the northern California city.

More than 200 officers, some of them ferried in aboard buses, lined up shoulder to shoulder and donned gas masks, then declared the crowd to be an unlawful assembly and fired volleys of tear gas as protesters turned and ran.

A few activists paused to pick up canisters and hurl them back at officers as they fled, while others threw rocks.

"This was peaceful until you came!" protesters shouted at police. Police later charged the plaza with batons and more tear gas to push protesters farther into center of the square.

The clashes in Oakland, which shot to the forefront of nationwide anti-Wall Street protests after a former Marine was badly injured in a rally last week, followed a day of rallies that drew some 5,000 activists at their peak and shuttered the busy Port of Oakland but failed to shut down the city.

At least one protester was carried away with an injury to his leg, and another who had been placed under arrest, his hands cuffed behind his back, lay on the ground with blood streaming down his face.

About three dozen activists were arrested, lined up seated along a street curb in plastic wrist restraints as they waited to be taken away by police.

Reuters