FOX31's Kasia Kerridge details the Safeway and Albertson's union strike as more stores across Colorado join in.

On Sunday, four stores went on strike including stores in Estes Park, Pueblo and Fountain, as well as a distribution center in Denver.

Safeway employees at a Denver store walked out Monday, expanding a strike that started this weekend. The strike started small with workers at three stores in Estes Park, Fountain and Pueblo, and a Denver distribution center.

The union representing Safeway store employees in Colorado has given the required 72-hour notice that the strike is set to begin one minute before midnight on Sunday.

Without a labor agreement in place with Union UFCW Local 7, Estes Park Safeway employees will go on strike on Sunday morning, joining just three other Safeway locations,