BOSTON -- Massachusetts risks losing hundreds of millions of dollars in gambling revenue if the state's gambling commission votes to open up the southeastern region to commercial casino developers, the Mashpee Wampanoag tribe warns.

The Mashpee, which has proposed a resort casino in Taunton, issued a statement and launched radio and TV ads in advance of a scheduled meeting on Thursday at which the commission will consider a plan to invite commercial bids for the sole state license in the region that until now has been carved out for a federally-recognized Indian tribe.

In a message posted on the commission's website, the panel's chairman, Stephen Crosby, said the plan under consideration would offer "the broadest range of options for the most parties," including the tribe.

But Cedric Cromwell, chairman of the Mashpee Wampanoag tribal council, said a vote by the commission to open up southeastern Massachusetts could result in four casinos being built in the state, rather than the three allowed under the 2011 casino law.

Should the state award a license to a commercial bidder, the tribe has promised to continue pursuit of a casino under a separate federal process. And should that casino eventually open, the tribe argues it would not be required to pay any revenue to the state, while it pulls business away from a competing casino in the region.

In the radio and TV ads, the tribe criticizes the commission for a lack of accountability.