A rolling strike of Starbucks baristas began Friday and grows to include about 300 of the coffee giant's shops across the U.S.

Starbucks baristas' fast-growing unfair labor practice strike is expected to hit historic levels Tuesday as hundreds of stores nationwide prepare to join walkouts at the coffee giant. The Starbucks Workers United strike,

Workers at more than a dozen Chicago area Starbucks were on strike Christmas Eve, union organizers said, as baristas escalated a national walkout that began in three cities, including Chicago, on Friday.