Kansas City, Mo. — A federal grand jury indicted two Chinese firms, an American firm and their principals on multiple counts related to tainted pet foods that sickened or killed perhaps thousands of pets last year and triggered the largest pet-food recall in the nation's history.

One of two indictments names Xuzhou Anying Biologic Technology Development Co. LTD (XAC), a Chinese maker of plant proteins, and its owner-manager, Mao Linzhun; and Suzhou Textiles, Silk, Light Industrial Products, Arts and Crafts, an export firm, and its top executive, Chen Zhen Hoe.

It accuses the Chinese businesses and their leaders of 13 felony counts of distributing adulterated food, and 13 felony charges of distribution of falsely branded food.

Both indictments call for fines against the companies and jail time for the executives, but it was unclear whether the prosecution actually can enforce fines and/or extradite officials from China.

The ingredient, wheat gluten, was tainted with melamine, a man-made substance often used in making plastics and fertilizer. It can make wheat gluten appear to have a higher protein content. The tainted foods also contained cyanuric acid. The combination of the two chemicals in pet food triggered wide-spread adverse health events for animals, according to a veterinary toxicology study performed last year at the University of California-Davis (see DVM Newsmagazine, January 2008, or go to http://dvmnews.com/).

The charges, brought by the U.S. attorney's office in Kansas City (where the shipments were received), result from a U.S. Food and Drug Administration investigation.

ChemNutra released a statement saying the company and the Millers deny all charges, had no knowledge of wrongdoing or intent to defraud and point out that the government isn't accusing its owners of knowing about the presence of melamine, but only of knowing the product was wrongly labeled.