HELENA, Mont. -

Montana tax authorities are seeking $3.4 million from a Wyoming coal company that used a practice under investigation by federal officials to place a value on the coal it was selling.
The state says the taxes are owed on sales between 2005 and 2007 from the Spring Creek mine near Decker, one of the largest coal mines in the U.S.
State District Judge Jeffrey Sherlock has scheduled a Tuesday hearing in a lawsuit Gillette-based Cloud Peak Energy filed to block the state's tax claim.
Cloud Peak calculated its taxes based on the price of coal sales to affiliated companies which then resold the fuel.
The U.S. Department of Interior is investigating whether the same practice was abused by companies including Cloud Peak to determine royalties on coal shipped to Asia.