Energy executives, mineral owners and Indian tribes, among others, are working with a state agency to halt coalbed methane development at a battlefield where Cheyenne and Sioux fought US troops in one of the bloodiest chapters of the country's history.

Sheridan, Wyoming-based Pinnacle Gas Resources has leases to explore for minerals at Montana's 3000 acre (12 square kilometre) Rosebud Battlefield Park, which hosts a potentially large deposit of coalbed methane.

However,