Amazon.com Inc. continues to expand its U.S. fulfillment center network. The e-retailer, No. 1 in the Internet Retailer 2016 Top 500 Guide, will open two facilities in California—in addition to the seven it already has in the state—and a second facility in Joliet, Ill., where it has operated a center since last year.

The announcements come a week after Amazon revealed new pricing for its Fulfillment By Amazon service, the service whereby merchants selling on the Amazon marketplace pay Amazon to store and ship their goods for them. In an email to sellers explaining the pricing it noted inventory levels in the network were “very high” last year and it was “accelerating the expansion of our fulfillment capacity.”

The new fulfillment centers in Tracy, Calif., and Eastvale, Calif., will be 1 million square feet each. Eastvale is about 50 miles east of Los Angeles and Tracy is in central California. Amazon already operates a fulfillment center in Tracy. Amazon says the two newly announced facilities will employ more than 1,500 full time.

The Joliet, Ill., facility will be 700,000 square feet and is next to the 500,000-square-foot facility it opened last year. The new and existing sites will fulfill orders for smaller goods, such as books and toys. Amazon says the new distribution center will hire more than 2,000 full-time workers. It already has more than 1,500 full-time employees in Joliet. When staffed up, Amazon will be the largest private employer in Will County, Illinois, southwest of Chicago, according to figures from the county’s Center for Economic Development.

Amazon has been aggressively expanding its fulfillment network, and, before today’s announcements, had 19 fulfillment centers in the works, according to supply chain consulting firm MWPVL International. Amazon has 76 large-scale fulfillment centers in the United States, plus at least 85 smaller facilities including sortation centers, where packages from elsewhere in e-retailer’s network are processed and handed off to the United States Postal Service and other delivery services for last-mile delivery. The e-retailer also has Prime Now hubs, which handle two-hours-or-less deliveries in urban areas.