Unionized doctors who work at student health clinics on southern University of California System campuses will begin a rolling strike on Saturday to protest the university's unfair labor practices.

Doctors, dentists and podiatrists at the UC campuses in UCLA, San Diego, Irvine, Riverside will start a  four-day strike to protest the school system's unfair labor practices in contract negotiations -- a charge the university denies, The Los Angeles Times reported.

Staff physicians at Northern and Central UC campuses -- Berkeley, Davis, San Francisco, Santa Cruz and Merced -- began their rolling strike on Thursday.

The walkout is meant to protest the administration's proclivity for not disclosing enough financial information about the university's resources that might affect "the contract bargaining and increase health clinic staffing," according to Sue Wilson, spokeswoman for the Union of American Physicians and Dentists.

By not providing this information, the school's administration show that "they think they are above the law -- that's why doctors are on the picket line today," Dr. Stuart Bussey, said in a statement.

It's the second time this year a strike was held on UC campuses. Members of the Union of American Physicians and Dentists previously held a one-day strike in late January at all 10 UC campuses.

Dwaine B. Duckett, UC's vice president for human resources, told The Times that school officials wished the union would have continued negotiations rather than call a second strike.

 "Strikes that negatively impact our students will not resolve a labor dispute," Duckett said in a statement.

The university said that management doctors would fill in as much as possible, but that some nonessential appointments for students were being moved. According to The Times, union members gave the university "plenty of notice so the clinics could plan to minimize the walkout's effect on students."