(NewsNation) — Néstor Isidro Pérez Salas, the top assassin for the Sinaloa cartel, has been extradited to the United States from Mexico to face gun, drug and witness retaliation charges that are all tied to his affiliation with Mexico’s most dangerous cartels and its jailed leader, Joaquín “El Chapo” Guzmán.

Federal officials announced Tuesday that Perez Salas will be arraigned Thursday on charges of importing cocaine and methamphetamine, firearms offenses and conspiracy to obstruct justice through murder.

In a second indictment, he is also charged with the leadership of a continuing criminal enterprise resulting in the deaths of numerous victims, including a confidential source for the Drug Enforcement Administration, fentanyl importation and trafficking, obstruction of justice by murdering an informant, kidnapping resulting in the deaths of eight people, including a minor, as well as firearms and money laundering offenses.

U.S. Attorney General Merrick Garland said Saturday that Perez Salas, known as “El Nini,” was one of the Sinaloa cartel’s lead assassins who was responsible for the murder, torture and kidnapping of rivals and witnesses who threatened the cartel’s criminal drug trafficking operation.

Here’s what is known about Pérez Salas and what his extradition to the United States means for the Sinaloa cartel’s criminal organization in the future.

Who is Néstor Isidro Pérez Salas, aka El Nini?

Pérez Salas, a 32-year-old Mexican national, commanded a security team known as the “Ninis,” which court documents describe as a particularly violent group of security personnel for the little Chapos or “Chapitos,” a faction of the Sinaloa Cartel run by Guzmán’s sons.

The nickname “Nini” is believed to be a reference to Mexican slang for “neither nor” to describe young people who neither work nor study, the Associated Press reported.

Authorities say Pérez Salas was involved in the torture of a Mexican federal agent in 2017. According to reports, Pérez Salas and others allegedly tortured the man for two hours and used a corkscrew to tear into his muscles. Authorities said that the corkscrew would then be removed and that the group would place hot chili peppers onto the wounds to inflict higher levels of pain.

What did Pérez Salas do for El Chapo’s Sinaloa cartel operation?

In addition to running security for the Sinaloa cartel, Pérez Salas was also involved in the operation’s drug trafficking operation.

In addition to running cocaine and other drugs into the U.S., the cartel has become notorious for its smuggling and distribution of fentanyl and other synthetic drugs into all 50 states, federal authorities maintain.

According to the U.S. Drug Enforcement Administration, fentanyl is responsible for about 700,000 overdose deaths in the United States each year. In a DEA report issued this year, officials said that the Sinaloa and Jalisco cartels have not only infiltrated all 50 states but have wiped out their competition for drug trafficking.

However, as the head of the Ninis security team, Pérez Salas oversaw a violent outfit that carried out gruesome acts of violence against those it took into their custody, the federal indictment indicated.

The group was responsible for taking rivals that were captured to a Chapitos-run ranch, where the prisoners would be executed. In some cases, they were fed alive or dead to tigers that were kept on the ranch as pets, authorities maintain.

In Tuesday’s indictment, federal officials alleged that under Salas’ direction, armed enforcers, known as sicarios, regularly used military-grade firearms – including machine guns and rocket launchers – to kidnap, torture and kill anyone who opposed the faction of the cartel. Officials say that the relentless violence has led to rampant bloodshed and taken the lives of untold victims.

What is Néstor Isidro Pérez Salas charged with?

Prior to being charged on Tuesday, Perez Salas was indicted twice previously by a grand jury,

In 2021, Pérez Salas was indicted by a grand jury in Washington, D.C., on charges he conspired to traffic cocaine and methamphetamine into the U.S. He was also charged with possession of machine guns and destructive devices as well as retaliation against witnesses.

In 2023, a New York grand jury indicted Pérez Salas on charges of engaging in a continuing criminal enterprise, conspiracy to import fentanyl, conspiracy to traffic fentanyl as well as possession of machine guns and other destructive devices. He also was charged with conspiracy to possess machine guns and destructive devices and conspiracy to launder money.

The DEA in 2023 offered a $3 million reward for the capture of Pérez Salas as part of a crackdown on cartel leaders. He was taken into custody last fall at a walled property located in the Sinaloa state capital of Culiacan in November.

What does the extradition of El Nini mean for the Sinaloa Cartel?

Following the news of the cartel leader’s extradition, President Joe Biden thanked Mexican President Andrés Manuel López Obrador for his cooperation in moving Pérez Salas to the U.S. to face charges.

“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, and to bring to justice the criminals and organizations producing, smuggling, and selling these lethal poisons in both of our countries,” Biden said in the statement.

The extraction of Pérez Salas is considered one of the most high-profile under López Obrador, according to the DEA.

The Chapos, overseen by El Chapo’s son, Ivan, and his other sons, was considered one of the most wanted targets of the DEA because of its power in its drug trafficking operation.

According to published reports, Pérez Salas’ extradition could lead to a charge in the hierarchal structure of the Sinaloa cartel that is expected to lead to a fight for succession and a wave of internal violence.

Biden called Pérez Salas’ capture “a good day for justice.”

Robert Almonte, a former U.S. marshal, deputy with the El Paso Police Department and NewsNation contributor, called Pérez Salas’ arrest and extradition “a great thing.” Almonte believes that the extradition and Tuesday’s indictment could factor into future moves within the top ranks of Sinaloa leadership given the sigificant role Pérez Salas played within the criminal organization.

“That guy was really, really bad,” Almonte told NewsNation on Tuesday. “He was bad news.”