United States Drug Enforcement Administration

ATLANTA - Roberto Lopez, a/k/a Shrek, a/k/a NWA, was sentenced to nearly two decades in federal prison following his convictions for cocaine trafficking and money laundering. Lopez, who was hiding in Mexico for more than a decade before his capture and expulsion to the United States, smuggled weapons to Mexico and helped manage a vast cocaine-smuggling network in support of high-level cartel leaders.

“Lopez’s sentence is the result of a determined and coordinated effort to dismantle the criminal network he was a part of,” said Michael J. Connolly, Acting Special Agent in Charge of the DEA Atlanta Field Division. “The success of this investigation demonstrates the strength of our Homeland Security Task Force partnerships and what we can accomplish when agencies work together.”                                                                                                                

“Before he went underground, Lopez was the head of domestic transportation for ruthless and far-reaching cartels that poured drugs into our community with military-level precision,” said U.S. Attorney Theodore S. Hertzberg. “Even if it takes decades, my office and our law enforcement partners in the Homeland Security Task Force will never cease our efforts to track and arrest fugitives in their hiding places and hold them accountable for their crimes.” 

According to U.S. Attorney Hertzberg, the charges, and other information presented in court: In the early 2000s, Edgar Valdez-Villareal, a/k/a “La Barbie,” was an infamous and ruthless enforcer for the Sinaloa and Beltran-Leyva Cartels in their war against the Gulf Cartel and the Zetas. Valdez also partnered with U.S.-based trucking businessman Carlos Montemayor to operate a distribution network that moved up to 300 kilograms of cocaine per week to Atlanta, Memphis, and other cities while smuggling cash back to Mexico in shipments carrying no less than $1 million per load. In just a six-month period, the organization distributed 1,500 kilograms of cocaine in Atlanta alone. 

The cartels’ operation is also estimated to have smuggled more than 1,000 rifles, 100-200 converted machineguns, and hundreds of magazines and ammunition drums into Mexico from the United States, along with silencers, night vision goggles, ballistic vests, helmets, and other tools of violence.

Lopez was the primary lieutenant for Valdez and Montemayor’s network, handling various logistics, including payments to truck drivers and stash house operators and the repackaging and transportation of money over the border. He was repeatedly intercepted on court-authorized wiretaps discussing loads of cocaine bound for the U.S. and shipments of cash destined for cartel leaders. When the investigation disrupted the organization, Lopez fled to Mexico, where he remained in hiding until his arrest there in 2024.

Roberto Lopez, 46, of Laredo, Texas and Mexico City, Mexico, was sentenced to 18 years, 10 months in prison to be followed by 5 years of supervised release. He pled guilty on May 19, 2026, to conspiracy to possess with intent to distribute cocaine and conspiracy to commit money laundering. Following his indictment on December 15, 2009, Lopez was arrested in Mexico City on June 27, 2024, and expelled by Mexico to the United States on August 12, 2025.

 In 2018, a federal judge in Atlanta sentenced Valdez to 49 years and 1 month in prison to be followed by 10 years of supervised release. In 2019, Montemayor was sentenced to 34 years and 3 months in prison to be followed by 10 years of supervised release.

This case was investigated by the Drug Enforcement Administration, with valuable assistance provided by the U.S. Marshals Service and the Department of Justice’s Office of International Affairs.

Assistant United States Attorneys Garrett L. Bradford and Elizabeth M. Hathaway and former U.S. Attorney John Horn prosecuted the case.

This prosecution is part of the Homeland Security Task Force (HSTF) initiative established by Executive Order 14159, Protecting the American People Against Invasion. The HSTF is a whole-of-government partnership dedicated to eliminating criminal cartels, foreign gangs, transnational criminal organizations, and human smuggling and trafficking rings operating in the United States and abroad. Through historic interagency collaboration, the HSTF directs the full might of United States law enforcement towards identifying, investigating, and prosecuting the full spectrum of crimes committed by these organizations, which have long fueled violence and instability within our borders. In performing this work, the HSTF places special emphasis on investigating and prosecuting those engaged in child trafficking or other crimes involving children. The HSTF further utilizes all available tools to prosecute and remove the most violent criminal aliens from the United States. The Atlanta Wilhelm HSTF comprises agents and officers from ATF, CGIS, DEA, FBI, ICE-HSI, IRS-CI, DOL-OIG, DSS, USMS, USPIS, and USSS, as well as numerous state and local agencies, with the prosecution being led by the U.S. Attorney’s Office for the Northern District of Georgia.