Another man in the drug ring, who was not directly connected to the death and therefore not charged with manslaughter, was recruited off the streets of Mexico and smuggled into the country expressly to peddle drugs in Ohio, the government said.

Image A FAMILY PROBLEM Dana Smiths three sons all became addicted to heroin, including the eldest, Arthur Eisel IV. Credit... Matt Eich for The New York Times

Fat on profits made largely in the United States, drug traffickers in Mexico are engaged there in a bloody war among themselves and with the government, which began a crackdown on them three years ago. Since then the violence, including assaults on the police and the army, has left more than 10,000 people dead.

But on this side of the border, the traffickers continue to expand their reach.

Drug Enforcement Administration officials say that Ohio is of particular concern because of the crisscrossing network of freeways here that make it well suited as a transshipment point. Anthony C. Marotta, who heads the agency’s Columbus office, said heroin tied to the Columbus-area dealers had been cropping up in nearby states like Indiana, Kentucky and West Virginia and as far away as the Baltimore area.

The case of Arthur Eisel and the men arrested for selling him heroin shows how the traffickers pushed their product and how in Mr. Eisel, already addicted to expensive pain killers because of a back injury, they found a ready customer for heroin, which was cheaper.

Investigators say that Arthur Eisel was not alone in switching from a prescription painkiller to heroin. It gives a similar, euphoric high at a fraction of the cost, $10 to $20 for a “balloon”  one dose, usually a gram or less  as opposed to upwards of $60 for a typical prescription pill dose on the street.

The traffickers found a ripe market in Grove City, a suburb of Columbus, as they have elsewhere in the nation. Drug seizures ebb and flow over the years, but the amount of heroin confiscated nationwide has been arcing up since the mid-90s, going from 370 kilograms in 1998 nationwide to about 600 kilograms  roughly $150 million worth of heroin  last year, though officials believe it is a small fraction of what is available on the street.