Joaquín Guzmán López, one of the sons of Sinaloa Cartel kingpin Joaquín “El Chapo” Guzmán, is the main suspect in the kidnapping that led to the capture of Ismael “El Mayo” Zambada on U.S. soil in July, the Mexico Federal Attorney General’s Office (FGR) announced Wednesday.

Mexican prosecutors are bringing charges against the younger Guzmán for apparently kidnapping Ismael “El Mayo” Zambada — an older drug boss from a rival faction of the cartel — forcing him onto the plane and flying to an airport near El Paso, Texas.

Guzmán López flew to the U.S. to turn himself in to U.S. authorities, but abducted Zambada Garcia before leaving Mexico, forcing him onto the plane, officials said.