ROANOKE, Va. -

The United States Department of Agriculture has busted several stores in Southwest Virginia for cheating the food stamps or SNAP system.

The black market for people to buy and sale food stamps, which today is known as SNAP benefits, is very much alive.

Here's how it works.

In some cases, the recipient gets a pre-paid card every month.  Take for instance the card is worth $200 dollars.  Instead of using it for groceries, you sale it for $100 cash.

According to federal documents, at least one convenience store in Danville, was doing that.  A case is pending against Samuel Pierce for violations that started in January 2009 and continued through this year.  Pierce owned the former A&P Grocery in Danville and later opened Asia Tire Service and Convenience Store.

Here are other stores found to be violating the SNAP program.  (List from USDA)

2013

57 Superette on Callands Rd., Chatham

Campbell Avenue Super Stop  on Campbell Ave., Lynchburg

*Jiffy Mart on Jefferson St., Danville

*West Stokes Convenience Market on W. Stokes St., Danville, Virginia

2012

*Alvaro Market on Walnut Ave., Vinton

Bedford Minute Market on Longwood Ave., Bedford

*M&R Stop Mart on Marshall Ave. SW, Roanoke

*M&S Stop Mart on 8th St. NW, Roanoke

*Royal Deli Mart  on Melrose Ave. NW, Roanoke

*Smoker's Choice on Liberty St., Martinsville

(* indicates "Permanent Disqualification" - store can never operate SNAP program unless the store ownership changes)