CHICAGO (AP) — Federal prosecutors in Chicago are dropping charges against a reputed drug trafficker for Mexico’s powerful Sinaloa cartel.

The reason? He seems to be dead.

The U.S. attorney’s office in Chicago filed a court document Thursday saying they’re dismissing the indictment against Juan Guzman Rocha. The filing says he appears to have been killed in cartel-related violence in 2011.

Among the around a dozen figures indicted along with Rocha in Chicago is the reputed head of the Sinaloa cartel, Joaquin ‘El Chapo’ Guzman. Mexican authorities captured him earlier this year.

Prosecutors say Rocha and his co-conspirators operated a $1 billion drug network extending to Chicago and other American cities.

Thursday’s filing says U.S. authorities don’t have Rocha’s death certificate but that the government is confident he is, in fact, dead.

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