Two new clashes in California's Los Angeles County jail system on Tuesday injured more than a dozen inmates and raised new concerns about the Sheriff's Department's effort to clamp down on the violence, according to recently released reports.

The disturbances at the Pitchess Detention Center, involving more than 100 black and Latino inmates, come nearly a month after the beginning of a series of racial brawls that has left two inmates dead and more than 100 injured.

The Sheriff's Department had achieved some success in reducing the violence. But officials said the latest violence involved some inmates who had just arrived in jail and were not involved in the earlier melees. Sheriff Lee Baca said Tuesday that the new flare-ups underscore the fact that the jails remain filled with agitators trying to fan racial tensions — even among new inmates.

"I think there are people within our jail system that are still trying to create those flashpoints," Baca said. "It is definitely going to continue because we don't have enough isolation cells available to separate everyone we'd like."

The Sheriff's Department has tried to segregate violent inmates whom they consider troublemakers who might be trying to start fights. But Baca said this is proving difficult and acknowledged that officials might never separate all of them.

"Our plan minimizes violence, but will never eliminate violence," Baca said. "This is not a school. This is not a sports team. These are criminals…. These are guys who are set to go off at any moment."

The Sheriff's Department has segregated about 500 inmates involved in the early conflicts. The department plans to transfer them to a few floors of the modern Twin Towers jail in downtown Los Angeles later this month and shift women housed there to a Lynwood jail facility. Officials said the fights at Pitchess have escalated in large part because violent inmates are housed together in large dorm-style rooms rather than in cells. The Twin Towers facility has cells.