Amazon.com is closing a trio of U.S. distribution centers, the first time it's closed a warehouse since 2006. Amazon said the closures in Munster, Ind., Red Rock, Nev., and Chambersburg, Pa. are part of a reorganization of its fulfillment network -- moving capacity to larger warehouses that can "better balance product mix and customer orders." The distribution centers slated for closure employ some 215 people.

Here's more from Amazon spokeswoman Patty Smith:

A variety of factors went into the plan to close these three buildings. We added approximately 3 million square feet of capacity in the North American fulfillment network in 2008, and will be converting a fulfillment center in Phoenix to accommodate our larger items (such as big screen TVs) and adding several hundred thousand sq feet to that facility. This additional capacity allows to the opportunity to better balance product mix and customer orders across the network year-round.

The 215 workers at the three warehouses slated for closure will receive pay through May 25, receive benefits through May 31, and get a minimum of 3 weeks severance pay, according to Smith, who said "eligible" workers will be offered the chance to transfer to other U.S. distribution centers.

Smith said Amazon now has "dozens" of fulfillment centers, but didn't provide the exact number. Amazon on its website says it has fulfillment centers in 12 U.S. states and 8 foreign countries.

Amazon seems to be paying a lot of attention to its warehouses lately. Amazon CEO Jeff Bezos recently spent a week working in a fulfillment center in Lexington, Ky.

The closure of the Munster warehouse was first reported by the Post-Tribune of Indiana, which noted that the facility opened just 18 months ago.