A five-day strike by Starbucks baristas had closed 59 stores as of Monday afternoon, according to the union organizing the workers.

The strike, which began Friday in Los Angeles, Chicago and Starbucks' hometown of Seattle, spread Monday to stores in Boston, Dallas and Portland, Ore. Workers in New York, Denver, Pittsburgh and other cities had also joined the strike over the weekend.

Starbucks workers have expanded their strike to more cities and closed 59 stores across the U.S. as of Monday, the union said amid stalled negotiations.