Negotiations between the Colorado union representing Safeway workers and the grocery chain have ended for the week without an agreement. Now, more stores are joining the strike, including Boulder, Lone Tree and Brighton.

More Colorado Safeway stores joined an ongoing strike as negotiations between the workers union and the grocer’s parent company stalled for the week Thursday night.

Negotiations have ended for the week, and additional stores will go on strike in the coming days, the union representing Safeway and Albertsons workers says.