(NewsNation) — Mexican cartel kingpin Ismael “El Mayo” Zambada was arrested near the Mexican border along with the son of notorious drug lord Joaquín “El Chapo” Guzmán.

The pair were arrested last Thursday after the two flew into an airport near El Paso, Texas. Zambada’s attorney says he was tricked by Joaquín Guzmán López and forced against his will to travel.

Zambada pleaded not guilty in El Paso federal court, waiving his court appearance Friday. He is set for another appearance Thursday.

Who is Ismael ‘El Mayo’ Zambada?

Zambada is the co-founder and figurehead of the vaunted Sinaloa cartel and is one of the most wanted men in all of Mexico.

He has been charged in California and New York, with prosecutors in February calling him the “principal leader of the criminal enterprise responsible for importing enormous quantities of narcotics into the United States.”

Prior to his arrest July 25, he had never been arrested, nor stepped foot in prison. He has been wanted in Mexico since 1998.

How does he relate to Joaquín ‘El Chapo’ Guzmán?

Both “El Chapo” and “El Mayo” co-founded the Sinaloa cartel and ran it together until the former’s capture in 2016. Since, it is widely believed that Zambada assumed full control of the organization.

Since Guzmán was sentenced to life imprisonment, his sons have been at odds with Zambada.

What is ‘El Mayo’ accused of?

Zambada is accused of a multitude of crimes, most of which relate to drug trafficking. In February, the Eastern District of New York charged him with distributing and conspiring to manufacture fentanyl.

According to Reuters, Zambada is facing charges of conspiracy to import narcotics, money laundering and criminal enterprise.

A filing in 2012 alleges two U.S. residents were kidnapped and murdered, in 2009 and 2010 respectively, under the instruction of both Guzmán and Zambada. Their bodies were eventually discovered in Juarez, Mexico.

‘El Chapo’ and Sinaloa cartel

A former Sinaloa cartel member told “NewsNation Prime” on Sunday that life grew more violent as the demand for drug increased.

Margarito “Jay” Flores Jr. became the main U.S. distributors for the Sinaloa cartel, working with Guzmán and Zambada before defecting to aid U.S. authorities in 2008.

Guzmán, one of the most infamous drug lords in history, is currently incarcerated at federal prison in Colorado after he was found guilty on 10 counts by a federal jury in Brooklyn in 2019.

ADX Florence houses Guzmán, as well as some of the world’s most dangerous and notorious criminals. It is widely considered to be the nation’s most secure prison.

In January of 2023, Guzmán wrote a letter to a federal judge, seeking a transfer to Mexico, citing what he called “inhumane” and “discriminatory” conditions in ADX Florence.