CHICAGO (CBS) — Federal agents conducted the single largest strike against one of the deadliest drug cartels in U.S. history, with operations in Chicago.

The U.S. Justice Department and Drug Enforcement Administration (DEA) and other law enforcement agencies engaged in multiple raids and arrests throughout the country, including Illinois.

CBS 2’s Suzanne Le Mignot has the exclusive story of how they were able to make a huge dent in the very profitable Cartel operations. She sat down with Special Agent In Charge Robert J. Bell for exclusive details of the operation.

It was series of nationwide raids, leading to more than 600 arrests and 350 indictments nationwide took place through the DEA’s “Project Python.” Those taken into custody work at all levels of the Cartel Jalisco New Generation or CJNG.

It’s one of the top two Mexican cartels operating in Chicago. Fifty of those arrests were made in Illinois, Indiana and Wisconsin.

Agents fanned out across the United States, culminating a six-month investigation with the primary goal of dismantling the upper echelon of CJNG and hoping to get closer to capturing its leader, one of the most wanted men in America.

“We got what we were hoping for, was results and an impact on CJNG that will make a difference now and will continue to make a difference going forward,” said Robert J. Bell, Special Agent in Charge, Chicago Field Division.

The CJNG drug trade is made up of heroin, cocaine, methamphetamine and fentanyl. Last year, more people died from fentanyl overdoses than by homicide in Cook County.

“The loss of life caused by opioid drugs and specifically fentanyl, illicit fentanyl, is astronomical and far surpasses the loss of life from firearms and from vehicles.” Bell said.

The cartel is headed by Nemesio Ruben Oseguera Cervantes, also known as El Mencho. His drug trade is estimated in the tens of billions of dollars. The state department has issued at $10 million reward for his capture.

The gang controls between one-third and two-thirds of the U.S. drug market. It is so violent that members leave piles of bodies in streets and hanging from overpasses in Mexico, and they fill the city of Guadalajara with mass graves. They carry machine guns and hand grenades. They once used rocket launchers to shoot down a Mexican military helicopter.

Among those now in custody during the six month long DEA operation with local and federal law enforcement are El Mencho’s son and daughter.

“DEA intelligence and information suggests that new generation is one of the five most violent criminal organizations in the world,” Bell said.

The cartel is known for sadistically torturing rivals in Mexico and dumping their bodies in the street.

“What we intend to do is to make the Chicago field division, Illinois, Indiana and Wisconsin, as inhospitable as possible for the new generation cartel to operate,” Bell noted. “We have a responsibility to address cartels like this who ultimately are causing the addiction, causing the overdoses and the overdose deaths.”

The Associated Press contributed to this story.

CBS 2 will have more on this story at 6:00.