About 17,000 AT&T wireline technicians and call center employees went on strike in California and Nevada today while filing an unfair labor charge to the National Labor Relations Board (NLRB) alleging that AT&T violated federal law.

“The company has shown disrespect to the bargaining process by changing the work assignments of workers without bargaining as required by federal law,” the Communications Workers of America (CWA) union said in its strike announcement. “Further, AT&T reneged on an agreement to resolve the dispute without any explanation.”

The CWA said that AT&T “is asking its workers to do more for less—keeping them from their families with unpredictable overtime, undercutting pay and advancement, offshoring good jobs, and pushing more health care costs onto employees.”