Four former chemical company executives and two lower-level employees have been charged in a January spill that contaminated a river and left 300,000 residents around West Virginia's capital without usable water for days.

A federal indictment unsealed Wednesday and announced by U.S. Attorney Boothe Goodwin charged former Freedom Industries presidents Gary Southern and Dennis P. Farrell and two others with failing to ensure that the company operated in an environmentally sound manner the tank that leaked a coal-cleaning chemical into the Elk River in Charleston.

Southern also faces fraud charges related to the company's bankruptcy case. Freedom filed for protection eight days after the Jan. 9 leak. - AP