2 Chinese companies and the American food products importer ChemNutra, have been indicted in the US for their alleged role in the tainted pet food scandal.

Prosecutors allege thousands of cats and dogs across the US died last year after traces of toxic chemical melamine were found in 150 brands of pet food.

They claim the contamination was traced to wheat protein imported from China by Las Vegas-based Chemnutra.

Chemnutra said it denied “any intent to defraud or knowledge of wrongdoing”.

‘Death or injury’

The two Chinese companies indicted are Xuzhou Anying Biologic Technology Development, and Suzhou Textiles, Silk, Light Industrial Products Arts and Crafts.

Bosses at the two firms, and the owners of Chemnutra, have also been charged individually.

Prosecutors say the affected animals died as a result of kidney failure.

“In today’s global economy, crimes that occur halfway around the world can seriously impact our lives,” said US Attorney John Wood.

Chemnutra said in a statement that prosecutors do not allege that its owners, Sally and Stephen Miller, “knew of the presence of melamine or any other substance that would cause death or injury to animals”.

“The Millers unequivocally support the government pursuing those with knowledge of the dangerous contaminants,” it added.

“However, they are deeply bothered by the government’s failure to make these important distinctions in its press release related to their indictment.”