The four sons of Sinaloa Cartel boss Joaquin "El Chapo" Guzman Loera, collectively known as "Los Chapitos," have denied allegations that they were major drug traffickers flooding the United States with fentanyl.

In a letter published by Mexican news outlet Milenio late Wednesday, El Chapo's sons wrote: "We have never produced, manufactured or marketed fentanyl or any of its derivatives." 

The letter was sent to Milenio by Jose Refugio Rodriguez, who confirmed to Reuters that he is a lawyer of the Guzman family, according to U.S. News.

In the letter, the Los Chapitos also denied being the leaders of the Sinaloa Cartel, saying they were just victims of an international misinformation campaign by firms, the media, and public figures that have painted them to be notorious drug traffickers.

"We are not the head of the Sinaloa Cartel nor are we interested in being... We are victims of persecution and have been made into scapegoats," they wrote.

The letter of Los Chapitos was a response to last month's press conference in Washington, where senior US officials said the Sinaloa Cartel was the main supplier of illegal fentanyl to the US.

The officials particularly blamed the Los Chapitos of the Sinaloa Cartel for worsening the opioid addiction epidemic in the US.

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El Chapo's Sons, Los Chapitos, Denied Feeding Rivals to Tiger

El Chapo's sons, Ovidio Guzman Lopez, Joaquin Guzman Lopez, Ivan Archivaldo Guzman Salazar, and Jesus Alfredo Guzman Salazar, are the Los Chapitos. 

Aside from accusations of drug trafficking and being the leader of one of the most notorious Mexican drug cartels, US prosecutors alleged that the Los Chapitos torture and sometimes feed Mexican federal agents and rivals to their pet tigers.

An indictment unsealed on April 14 in the New York Southern District revealed that the Sinaloa Cartel would use the animals to feed many of their victims, dead or alive, to the tigers kept by two sons of El Chapo, namely Ivan Archivaldo and Jesus Alfredo.

But in the letter, the Los Chapitos denied such accusations, saying they do not even have tigers.

CBS News reported that the US indictment also noted that the Los Chapitos used corkscrews, electrocution, hot chiles, and waterboarding to torture their rivals and associates who refused to pay debts.

The New York Post also reported that the victims were disposed of once they gave out the information the cartel members wanted. The indictment further noted that one Sinaloa Cartel member used a corkscrew to remove a muscle of a Mexican federal law enforcement officer.

However, Los Chapitos claimed that many people and groups were claiming to be Sinaloa Cartel's members and leaders for their own advantage.

"What does exist is a countless number of small and large groups that have their base of operations in the state or are made up of people from Sinaloa and operate in other parts of the country or even in other parts of the world," El Chapo's sons noted.

They added: "These groups operate completely independently of others and are not accountable to us, nor do we request them."

The US Department of Justice charged 28 members and leaders of the Sinaloa Cartel, including Los Chapitos, last month. The indictment charged the four sons of El Chapo with large-scale drug trafficking, money laundering, and "violent crimes," Daily Mail reported.

Reward for Sinaloa Cartel Boss' Sons, Known as Los Chapitos, Doubled by US

The US has recently doubled its reward for information leading to the arrest of two of Sinaloa Cartel boss El Chapo's sons.

According to Daily Mail, the Drug Enforcement Administration (DEA) now offered $10 million apiece for information leading to the capture or conviction of Ivan Archivaldo Guzman Salazar and Jesus Alfredo Guzman Salazar.

The reward for Ivan Archivaldo and Jesus Alfredo is now among the highest offered by federal officials in US history.

The increase in the reward was announced after the DEA added Ivan Archivaldo to its 10 most-wanted drug traffickers list, joining his older brother, Jesus Alfredo.

El Chapo's four sons reportedly operate half of the Sinaloa Cartel, while the other half is managed by its co-founder Ismael "El Mayo" Zambada.

Los Chapitos had reportedly assumed leadership roles in the Sinaloa Cartel after their father was arrested and extradited to the U.S.

Only three of the Los Chapitos remain at large as Ovidio Guzman was already arrested last January 5 by Mexican authorities in Mexico's Sinaloa state. He remains detained in Mexico pending extradition proceedings to the U.S.

READ MORE: Sinaloa Cartel Continues Growing Despite El Chapo's Absence

This article is owned by Latin Post.

Written by: Mary Webber

WATCH: Sinaloa Cartel Members, Including El Chapo's Sons, Charged by DOJ - From ABC 7 Chicago