El Chapo's son Ovidio Lopez and Sinaloa Cartel co-founder Ismael 'El Mayo' Zambada are in US custody after $20 million reward offered for kingpins who raked in $11 BILLION a year

Two Mexican drug kingpin, including the son of notorious cartel boss El Chapo, have been arrested and are in US custody.

Ismael 'El Mayo' Zambada, the co-founder of the Sinaloa drug cartel, and Joaquín Guzmán López surrendered to American law enforcement on Thursday.

Zambada, 76, founded the Sinaloa Cartel along with now-jailed drug lord Joaquin 'El Chapo' Guzman, and faces a litany of indictments for crimes relating to drug trafficking and organized crime in the US.

Joaquín Guzmán Lopez is one of El Chapo's sons and was elevated to the cartel's top leadership in 2017 when his father was extradited to the US. 

The pair were arrested in El Paso, Texas, after getting off a private plane. What prompted them to turn themselves in after years as most-wanted is unclear.

Sources told DailyMail.com that the FBI flew the plane to El Paso from Mexico with them on board. 

Zambada lived a simple life behind the scenes at his El Alamo compound, in contrast to El Chapo's larger than life persona, and was suffering from diabetes.

He was reportedly in communication with American law enforcement for the past three years at least, discussing the possibility of surrendering.

This was a marked contrast form 2010 where he said in a rare interview he 'I'd like to think so, that I'd kill myself' if he faced police capture.

Lopez is expected to face the Federal District Court in Chicago in coming days, but where Zambada will be arraigned is not yet known.

Attorney-General Merrick Garland called the cartel one of the most violent and powerful drug trafficking organizations in the world as he detailed the arrests.

'El Mayo and Guzmán López join a growing list of Sinaloa Cartel leaders and associates whom the Justice Department is holding accountable in the US,' he said.

Garland said others from the cartel now behind bars included El Chapo and another of his sons and alleged leader of the Cartel, Ovidio Guzmán López. 

The alleged main hitman of the cartel, Néstor Isidro 'El Nini' Pérez Salas, was also in American custody, he said.

American federal prosecutors in February charged Zambada with conspiracy to make and distribute fentanyl, but he has never been behind bars.

The US State Department earlier put an up to $15 million bounty on Zambada's head, for any information leading to his arrest or conviction.

A $5 million bounty was offered for Lopez's arrest.

Joaquín's brother Ovidio Guzmán López was also arrested in Mexico, and extradited to the US in September to face his own long list of charges. 

After El Chapo's extradition, his criminal empire was inherited by four of his sons - known as Los Chapitos, or Little Chapos - who took over his faction of the cartel and became some of the biggest exporters of fentanyl to the US. 

El Mayo and Los Chapitos have had a fractious relationship since El Chapo's extradition, and the arrests of the two traffickers may trigger instability or even violence in Mexico.

Garland said fentanyl was the leading cause of death for Americans between the ages of 18 and 45.

'The Department of Justice will not rest until every leader, member, and associate of the cartels responsible for poisoning our communities is held accountable,' he said.

Zambada helped 'El Chapo' construct a network that has exerted its influence in illicit markets as close as the US and Colombia, and as far as New Zealand and Russia.

They distributed cocaine, heroin and other drugs while tapping into the lucrative human trafficking business.

Under the watch of the 76-year-old, the criminal organization has been able to haul in $11 billion based on seizures and pricing provided by the Drug Enforcement Agency.

'El Mayo' positioned himself as one of the richest men in the narcotics, earning $3 billion since 2001, despite his aversion to showing off his wealth.

Mike Vigil, who once led the DEA's international operations, recognized 'El Mayo's' business smarts as the head of a criminal syndicate that has spread its wealth and laundered its unlawful profits through international banks and companies.

The American agency tasked with battling drug smuggling and distribution has pointed out 250 business that have benefited from the Sinaloa Cartel's illicit earnings.

They included a dairy company, water park and a daycare center allegedly operated by his daughter Maria Teresa.

'Even though he's only had maybe an elementary-school education, he's received a Harvard-level education from some of the most prolific, knowledgeable and astute drug lords that Mexico has ever had,' Vigil told Bloomberg in 2018.

In a 2010 interview with Proceso, 'El Mayo', admitted the possibility of being arrested created a sense of 'panic' despite how hard to he worked to maintain a low profile in public and wouldn't rule out committing suicide if it meant avoiding doing time in jail.

'I don't know if I'd have the courage to kill myself. I'd like to think so, that I'd kill myself,' he said.

A Sinaloa Cartel faction led by the sons of El Chapo has allegedly claimed responsibility for the kidnapping of 66 people in the northern Mexican city of Culiacán in March.

A series of narco mantas - or banners were found hanging from four highway overpasses and bridges before Tuesday morning's rush hour traffic. 

The banners insisted the abductions were in response a rash of criminal incidents orchestrated by a home invasion gang, which some claim is led by law enforcement agents.

Each display featured a banner with a message signed off with the initials of El Chapo's son, Iván Archivaldo Guzmán, and had the pictures of the gang's four leaders.

More to come.