About 45,000 grocery workers have authorized a strike at Ralphs, Albertsons, Vons and Pavilions stores in Southern California to protest unfair labor practices.

The union representing more than 45,000 grocery store workers from Santa Barbara to San Diego voted Wednesday to authorize a strike against supermarket chains Albertsons and Kroger. No date has been set for a strike.

Workers at Albertsons, Pavilions, Ralphs and Vons grocery stores will begin preparations Thursday for a possible strike. Local 770 of the United Food and Commercial Workers union, representing approximately 45,