The Starbucks strike spread to more than 300 stores in the United States on Tuesday. According to the workers’ union, around 5,000 workers are expected to take part in the five-day industrial action, which ends later today.

Workers at more than 60 stores walked off their jobs in 12 major cities on Monday. The Starbucks Workers Union, which represents workers at 525 stores across the country, predicts the Christmas Eve expansion will be the largest yet.

“Half the baristas in my store drive 30 minutes one way because they can’t afford to live closer to work,” Lauren Hollingsworth, a barista from Ashland, Oregon, said in a union statement. “These strikes are a first act of strength,” she added.

The five day strike started on Fridaybringing it into play during the holiday shopping season, and expanded by More stores opened in more cities over the weekend, with workers protesting a lack of progress in contract negotiations with the Seattle-based company.

According to the union, the company has not fulfilled its commitment made in February to reach a collective agreement this year.

Starbucks proposed a stimulus package that includes no new pay increases for unionized baristas and includes a 1.5% increase in coming years, the union said Friday.

Starbucks said Workers United ended talks early this week. According to the coffee chain, wages and benefits already amount to $30 an hour for those who work at least 20 hours a week.

The union also wants Starbucks to resolve outstanding legal issues, including hundreds of unfair labor practice charges that workers have filed with the National Labor Relations Board. The agency has also opened or settled hundreds of lawsuits against Amazon. On Thursday, a day before the Starbucks strikes, the Teamsters union formed announced strikes to seven Amazon delivery centers.

Starbucks did not immediately respond to a request for comment.