MEXICO CITY (AP) — About 10 million gallons (40,000 cubic meters) of contaminated wastewater have spilled into rivers from a mine in northern Mexico, and federal officials announced Sunday they are restricting water supply to cities and towns in the country’s north, including the Sonora state capital of Hermosillo.

The National Water Commission said it was monitoring chemicals in the Bacanuchi and Sonora rivers following this week’s spill at the Buenavista copper mine in Cananea, about 25 miles (40 kilometers) south of the U.S. border.

The state’s civil defense office issued a statement on its Facebook page denying rumors that the contamination includes cyanide, which it said it not used in copper mining.

The water agency says towns affected include Arizpe, Banamichi, San Felipe de Jesus, Aconchi, Baviacora and Ures, as well as Hermosillo. However, it said the state capital receives only 3 percent of its water from the river.

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