Washington DC - A top assassin in Mexico's Sinaloa drug cartel was extradited Saturday to the US, the head of the Department of Justice said, where he will face charges linked to drug smuggling, murder, and torture.

Nestor Isidro Perez Salas, known as "El Nini," was one of the Sinaloa Cartel's "lead sicarios, or assassins, and was responsible for the murder, torture and kidnapping of rivals and witnesses who threatened the cartel's criminal drug trafficking enterprise," US Attorney General Merrick Garland said in a statement after the extradition Saturday morning.

"We also allege El Nini was a part of the Sinaloa Cartel's production and sale of fentanyl, including in the United States."

The US had offered up to $3 million for information leading to the arrest of Perez Salas.

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He is thought to be a close associate of the sons of Mexican drug lord Joaquin "El Chapo" Guzman, who is serving a life sentence in the US.

He was arrested in the northwest Mexican city of Culiacan in November 2023, less than a week after US President Joe Biden and Mexican President Andres Manuel Lopez Obrador pledged to coordinate more closely on fighting drug trafficking, especially that of the powerful synthetic drug fentanyl.

In a statement thanking Lopez Obrador, Biden said Perez Salas played a "prominent" role in the Sinaloa cartel, which he called "one of the deadliest drug trafficking enterprises in the world."

"Our governments will continue to work together to attack the fentanyl and synthetic drug epidemic that is killing so many people in our homelands and globally," Biden said.

The US saw more than 107,000 drug overdose deaths in 2023, according to the Centers for Disease Control and Prevention. Fentanyl accounted for about 70% of them.

The US government says fentanyl is often made from products sourced in China, and then is smuggled across the border from Mexico by drug traffickers, especially the Sinaloa cartel.