A federal grand jury has indicted a 38-year-old man described as a principal leader of Mexico's Gulf Cartel on federal drug and immigration charges.
Rafael Cardenas Vela was arrested last month following a traffic stop in Port Isabel.
Federal officials say Vela is accused of participating in drug and money laundering conspiracies and procuring fraudulent Visa documents.
Cardenas Vela is the nephew of former Gulf cartel leader Osiel Cardenas Guillen, convicted of federal drug charges last year and sentenced to 25 years in prison.
The Gulf cartel is based in Matamoros, Mexico, across the border from Brownsville.
The cartel controls major drug smuggling corridors between Reynosa and Matamoros.
Under Cardenas Guillen's leadership, the Gulf cartel spawned the Zetas, which evolved into a ruthless rival.