A high-ranking member of the Sinaloa cartel in Mexico pleaded guilty to drug trafficking a year ago and has been cooperating with authorities, federal prosecutors in Chicago announced Thursday.

Jesus Vicente Zambada Niebla pleaded guilty in April 2013 to one count of conspiracy to possess with intent to distribute multiple kilograms of cocaine and heroin between 2005 and 2008, according to a plea agreement unsealed Thursday.

Co-defendants in the case are Joaquin "El Chapo" Guzman, the head of the cartel who was captured in Mexico in February, and Zambada's father, Ismael "El Mayo" Zambada-Garcia, considered to be a close ally of Guzman's in running the cartel.

According to the documents, Jesus Zambada told authorities he was a "trusted lieutenant" for his father, acting as a surrogate and logistical coordinator for cartel operations.

Zambada was indicted in Chicago in 2009, and extradited after his arrest in Mexico City in 2010. The Sinaloa cartel has a large presence in Chicago.

The plea agreement also states Zambada was responsible for distributing multiple tons of cocaine, sometimes moving hundreds of kilograms of the drug on a weekly basis, between 2005 and 2008.

The documents do not say whether Zambada's cooperation included information that led to Guzman's arrest.

Zachary T. Fardon, the U.S. Attorney for the Northern District of Illinois, said Zambada faces a maximum sentence of life in prison. A sentencing date has not been set.

Zambada Niebla is son of Ismael Zambada, a Sinaloa cartel leader known as "El Mayo". In Mexico Zambada junior is known as "Vicentillo".