Nemesio Oseguera Cervantes (El Mencho): Who Was He and Why Was He So Notorious?

How does someone go from wearing a police badge to becoming one of the most feared drug traffickers on Earth?

That’s the story of Nemesio Oseguera Cervantes, better known as El Mencho, the founder and long-time leader of the Jalisco New Generation Cartel (CJNG).

When people talk about the most powerful drug traffickers in the world today, his name often rises to the top. 

Once a police officer in western Mexico, Oseguera went on to become one of the world’s most wanted fugitives. The United States alone offered a staggering $15 million bounty for information leading to his arrest. 

For years, U.S. and Mexican authorities described him as a mastermind behind a global narcotics empire and as Mexico’s most powerful cartel boss, especially after the arrest of Joaquín Guzmán, widely known as “El Chapo", in the last decade.

But how did this transformation happen? And why has his name become synonymous with violence, power, and one of the fastest-growing criminal organisations in modern history?

In a dramatic and violent turn of events in 2026, Mexican and international authorities confirmed the death of the infamous drug lord Nemesio Oseguera Cervantes, widely known as El Mencho, marking a crucial moment in the long and complex Mexican drug war.

For over a decade, El Mencho led one of the most powerful and feared criminal organisations in the world – the Jalisco New Generation Cartel (CJNG) – until he died in a Mexican military operation in Tapalpa, Jalisco, in February 2026. 

His influence and ruthless leadership reshaped organised crime both in Mexico and internationally, and his violent legacy continues to affect millions. 

For years, El Mencho topped the U.S. Federal Bureau of Investigation’s Most Wanted list, with a multi-million-dollar reward offered for information leading to his capture. He’s widely considered one of the most powerful and dangerous drug traffickers alive. 

Under his leadership, CJNG grew from a regional organisation into a sprawling criminal empire involved in trafficking cocaine, methamphetamine, heroin, and, particularly, fentanyl – a synthetic opioid linked to thousands of overdose deaths in the United States. 

Unlike older cartels that preferred staying in the shadows, CJNG made headlines with bold, public shows of force, including attacks on military helicopters and the use of explosive-equipped drones. 

Employing speed, strategy and brutality, CJNG’s reach stretched far beyond Mexico’s borders. By the mid-2020s, authorities in North America, Europe, Africa, and Asia reported seeing the cartel’s drug flow, money laundering networks, and violent methods impact their communities. 

This global footprint is one reason law enforcement labelled CJNG one of the most dangerous criminal groups in the world. 

El Mencho was born on July 17, 1966, in a rural part of Michoacán, Mexico, into an impoverished farming family. Little about his early life hinted at the violent path ahead.

Like many young Mexicans seeking opportunity, he migrated to the U.S. in the 1980s. There, he encountered drug trafficking networks and was eventually #arrested on heroin distribution charges.

After serving a prison sentence, he was deported back to Mexico, where he re-entered the criminal world with new contacts and a hardened ambition.

After his return, Oseguera reportedly worked as a police officer in the western state of Jalisco. But history and TV shows like Power have proved that enforcement agencies and corruption often intersect. 

Serving in law enforcement may have provided insight into operational structures, intelligence systems, and vulnerabilities.

Knowledge is power. And he used it. It didn’t take long before he resumed criminal activities. Slowly and strategically, he built influence in the narcotics trade, operating in the shadows while cultivating alliances.

Upon his return to Mexico, El Mencho integrated into the Milenio Cartel, a significant criminal organisation that dominated drug operations in the western states. Later, in the 2000s, Mexican authorities dismantled major cartels, and power structures began to crumble.

When top cartel figures were arrested or killed, opportunities presented themselves, and El Mencho seized them. He teamed up with fellow trafficker Erik Valencia Salazar (“El 85”) and began building what would become the CJNG.

CJNG emerged around 2007–2010, positioning itself as both an aggressive rival to older cartels, with up to 20,000 members by American government estimates, and a force claiming to protect local communities — a tactic often common in organised crime to build social support. 

Under El Mencho’s leadership, CJNG was distinctive for its military-style tactics, including armoured convoys, heavy firearms, and tactical coordination. 

This was not the old mafia. The cartel also employed psychological warfare, paramilitary capability, strategic intelligence, and public displays of power. 

CJNG expanded aggressively across Mexico. It built alliances, crushed rivals, and took control of key drug trafficking routes. 

CJNG became known for extreme violence. Public executions, mass graves, and attacks on security forces sent a clear message: challenge us, and face consequences.

In 2015, CJNG fighters even shot down a Mexican military helicopter during an operation targeting El Mencho. That event stunned the nation.

After El Mencho’s death in February 2026, vehicles were burnt and blockades set across dozens of Mexican states, leaving security forces on alert. 

Reports indicated at least 14 deaths in post-operation violence, with several Mexican guards killed and civilians wounded in clashes. 

CJNG isn’t limited to Mexico. It’s deeply involved in trafficking cocaine, methamphetamine, and fentanyl into the United States and beyond. Authorities allege that the cartel runs a global distribution network reaching North America, Europe, and Asia.

The U.S. government described the cartel’s fentanyl distribution as a “reign of terror", resulting in criminal designation and billions in sanctions.

CJNG’s revenue reportedly reached multi-billion-dollar levels, sustained by drug sales, extortion, kidnapping, and laundering operations spanning continents. 

This made El Mencho more than a trafficker — he was a central figure in transnational organised crime.

Let’s zoom out and look at the big picture.

• Migration to the U.S.

• Arrest and deportation

• Entry into organised crime in Mexico

• Formation of CJNG

• Violent clashes with rivals

• Rapid territorial expansion

• CJNG shoots down a military helicopter

• Global media attention intensifies

U.S. authorities placed El Mencho on the DEA’s most wanted list. The U.S. government announced a multi-million-dollar reward for information leading to his capture.

Despite numerous operations, El Mencho has remained elusive. Rumours of his arrest or death occasionally surface, but none are confirmed.

It’s like chasing a ghost.

Mexican federal forces, supported by U.S. intelligence, launched a high-stakes operation in Tapalpa, Jalisco, targeting El Mencho. 

Heavy resistance broke out, but El Mencho was fatally wounded and later died while being transported to Mexico City. 

Following his death, CJNG loyalists initiated widespread retaliation, blocking roads, burning vehicles, and triggering uncertain security conditions across regions. 

Governments issued travel warnings, and several cities temporarily shut down schools and services due to security concerns. 

El Mencho’s death does not mean the end of CJNG, but it raises critical questions about the cycle of cartel violence. Targeting leaders alone often fails to reduce recruitment or disband criminal structures. 

Cartels adapt, restructure, and recruit aggressively from vulnerable populations, meaning the underlying issues persist even after high-profile takedowns.