Payless ShoeSource is set to close 2,100 locations in the United States and Puerto Rico, including 18 stores in the greater Valley region. The retail chain, which filed for Chapter 11 bankruptcy in April 2017, also plans to shut down its online operations. Liquidation sales began Sunday and stores across the country will begin closing in March, but most are scheduled to stay open until May. Locations set for closure in L.A. County include: Van Nuys, Panorama City, Pacoima, Burbank, Sylmar, two in Northridge, Reseda, North Hollywood, Canoga Park, two in Santa Clarita, Lancaster and three in Palmdale. Locations in Ventura County include: Janss Marketplace in Thousand Oaks and Sycamore Square in Simi Valley. Payless, headquartered in Topeka, Kan., has more than 3,600 locations in 40 countries and more than 18,000 employees, according to its website.