MONTPELIER, Vt. (AP) -- A group of dairy farmers is suing four milk marketing firms, saying they've engaged in monopolizing the market into which farmers have had to sell milk, fixed prices and created an economic crisis in the Northeast dairy industry.

The Washington-based law firm Cohen Milstein says it expects many farmers will join a class action suit against Kansas City-based Dairy Farmers of America and Dallas-based Dean Foods Co.

Plaintiffs accuse DFA and Dean Foods of monopolizing a level of distribution of fluid milk in the Northeast and forcing farmers to join DFA or its marketing affiliate Dairy Marketing Services to survive.

DMS and HP Hood also were named as defendants. The companies did not immediately respond to requests for comments.

Copyright 2009 The AP.

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