CLEVELAND -- Two men arrested on drug trafficking charges could face more serious charges because prosecutors say their lethal drug mix caused at least one death.

Rafael Rivera-Torres II, 43, and Ralph Torres, 65, both of Cleveland, were arrested after authorities say heroin packets that they were selling are believed to have caused at least one death and other overdoses on Cleveland's near West Side Monday and Tuesday.

Today the Cuyahoga County prosecutor's office filed involuntary manslaughter complaints against each man with the Cuyahoga County Court of Common Pleas. The complaint is not an indictment, and the case will have to be presented to the grand jury.

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The complaints against each say they "unlawfully did cause the death of Christopher Vance" and "such death was the proximate result of Ralph Torres and or Rafael Torres committing or attempting to commit the felony offense of drug trafficking."

The prosecutor's office also filed four felony complaints of trafficking against Torres and two against Rivera-Torres and a felony complaint of drug possession against Torres.

Cuyahoga County Sheriff Frank Bova said the heroin these suspects were selling is especially dangerous.

"This heroin was cut with large amounts of fentanyl and is being referred to as 'Chine White,' " he said. "Fentanyl is an extremely potent prescription medication that is 80 times more powerful than pure heroin. People have already died, and the heroin being sold by these suspects and their organization is still being sold on our streets."