Eighteen people have been indicted in a multi-million dollar copper theft ring at an Arizona mine, state Attorney General Tom Horne announced Tuesday.

Horne said employees of the Asarco LLC mine at Hayden were involved in the thefts.

The case began after a traffic stop last year of a truck carrying nearly $180,000 of raw copper that had been stolen from the Asarco mine in Hayden.

The Department of Public Safety says Asarco, LLC employees were involved in the theft of nearly $10 million of the metal. Defendants who had been working at the mine have been fired.

Other defendants are accused of driving the copper loads to recyclers in California and Arizona, who would buy it for a fraction of market value.

The attorney general says the recyclers would blacken the copper so it could pass easily through customs on its way to China.