Pictured: Sinaloa Cartel's Top Assassin, Suspected in Killing of DEA Source, Brought into US in Handcuffs

The alleged Sinaloa Cartel leader and lead assassin known as "El Nini," wanted for the killing of a Drug Enforcement Administration (DEA) confidential source and several others, was brought into the U.S. in chains on Tuesday, according to the Department of Justice.

Néstor Isidro Pérez Salas, allegedly the Sinaloa Cartel's lead sicario, or assassin, was extradited on May 25 to face the charges laid out in an indictment in the Southern District of New York and another indictment in Washington, D.C.

"Today, El Nini joins the growing list of cartel leaders and associates extradited to the United States and held accountable in an American courtroom," Attorney General Merrick B. Garland said in a statement.

"We allege 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. This includes killing a Drug Enforcement Administration (DEA) confidential source and killing others in retaliation for the confidential source's cooperation," Garland said.

"We also allege El Nini was a part of the Sinaloa Cartel's production and sale of fentanyl, including in the United States. I am grateful to our Mexican government counterparts for their extraordinary efforts in apprehending and extraditing El Nini. The Justice Department will always be relentless in its pursuit of the cartels responsible for flooding our communities with fentanyl and other drugs," Garland said.

In the New York indictment, Pérez Salas is charged with participating in a continuing criminal enterprise resulting in death; conspiring to import fentanyl into the U.S.; conspiring to distribute and possess with intent to distribute fentanyl; using, carrying, and possessing machine guns and destructive devices in connection with the continuing criminal enterprise and the fentanyl importation and trafficking conspiracies; conspiring to use, carry, and possess machine guns and destructive devices in connection with the continuing criminal enterprise and the fentanyl importation and trafficking conspiracies; conspiring to launder money; obstruction of justice by retaliating against an informant through murder; conspiring to obstruct justice by retaliating against an informant through murder; kidnapping resulting in death, including of a minor; and conspiring to commit kidnapping resulting in death, including of a minor.

In the District of Columbia indictment, Pérez Salas is charged with conspiring to import cocaine and methamphetamine into the U.S.; using, carrying, and possessing machine guns and destructive devices in connection with the cocaine and methamphetamine conspiracy; and conspiracy to obstruct justice by retaliating against a witness and informant through murder.

The Sinaloa Cartel is one of Mexico's most powerful cartels, formerly led by the notorious "El Chapo," Joaquin Archivaldo Guzman Loera, and more recently led by his sons, known collectively as the "Chapitos."

Pérez Salas is allegedly a commander of the "Ninis," described by authorities as a violent group tasked with providing security for the Chapitos. In that role, in October 2023, Pérez Salas and sicarios under his command allegedly kidnapped a confidential source and 10 other victims in Mexico - including a U.S. citizen - believed to be connected to the confidential source. They allegedly killed eight of the kidnapped victims, including a 13-year-old boy.

-With reporting from TMX.