Updated

An elderly Ohio couple has been criminally charged after allegedly dumping 55 gallons of toxic cyanide into a storm sewer, causing the death of tens of thousands of fish and other wildlife in the Rocky River.

Renato Montorsi, 79, and his wife Teresina, 74, of Grafton, are charged with conspiracy and obstruction of justice, Cleveland.com reported. The pair own a coin and precious metal business and previously operated a metal-plating company that used cyanide.

"Mr. Montorsi chose to use the river behind us as his own dump," U.S. Attorney Steven Dettelbach reportedly said at a news conference Wednesday. "Nearly every fish in a three-mile stretch -- about 30,000 -- was killed."

Renato Montorsi is also accused of violating the Clean Water Act, according to the website.

A massive number of dead or dying fish and other wildlife washed up along the East Branch of the Rocky River on April 22 -- Earth Day -- the website reported.

Investigators claim Renato Montorsi first tried to get rid of the highly toxic cyanide in a municipal trash receptacle, but said garbage collectors refused to handle the hazardous chemical. Environmental regulations require that cyanide be disposed of by workers licensed to handle the liquid.

Instead, Dettelbach said, Montorsi poured the cyanide into a sewer, which eventually contaminated parts of the Rocky River, according to the website.

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