The killing of Nemesio Oseguera Cervantes, known as “El Mencho”, has set off a wave of violence and fire in Mexico.
Oseguera, 59, was the leader and one of the founders of the Jalisco New Generation Cartel (CJNG), an organisation known for being the country's most violent drug cartel.
In 2024, the US government had offered a reward of upto $15 million for information which could lead to the arrest of the elusive cartel boss. However, Oseguera evaded arrest for many years while some of his family members involved in the operations were captured and convicted. Oseguera’s son and successor, Rubén Oseguera known as “El Menchito,” was found guilty of drug trafficking and illegal use of firearms in Washington last year.
Soon after the killing of Oseguera on Sunday, armed groups blocked roads and set fire to supermarkets, banks and vehicles. The chaos has led to about 252 road closures in about 20 states across Mexico, the government's security cabinet reported. The biggest reports of violent incidents came from Jalisco, where the cartel began.
Cártel de Jalisco Nueva Generación (CJNG)
The CJNG, which was formed in 2009, is one of Mexico’s most powerful criminal organisations. In a 2025 report, the US government designated the Jalisco state based crime syndicate a terrorist organisation. Since its formation, the group took on an agressive approach, expanding over time, to about 27 of Mexico's 32 states.
The group is responsible for the trafficking of high quantities of cocaine, heroin, and methamphetamine into the country, which also creates their biggest revenue. They are also involved in extortion and money laundering. According to a 2023 report by the LA Times both the Jalisco cartel and its biggest rival, Sinaloa had about 45,000 members with brokers in more than 100 countries.
Many from the group who were arrested by the Spanish government in 2025 were involved in smuggling large amounts of the drugs inside industrial machinery from south America. The drugs were distributed to Spain and other European countries, El País reported.
According to the US Department of Justice, Oseguera’s leadership led to the group being responsible for large-scale homicides against rival trafficking groups and Mexico's law enforcement.
The group is known for its high-profile crimes and extreme violent methods since its appearance in 2009. After mass murders, they often leave dismembered or burned bodies in public areas where they can be found, including in vehicles and on bridges. There were also reports of the group’s members being forced to cannibalise its victims as part of training. In 2015, they made headlines with the drowning of an army helicopter using rocket-propelled grenades. The attack killed dozens of state officials.
The group has also been found to be behind assassination attempts of Mexican government officials and was behind the 2020 attack against Omar Garcia Harfuch, the secretary of security of Claudia Sheinbaum’s government.
The CJNG uses a franchise model to operate. The group delegates each phase of drug trafficking to a specialised link in its chain. They have regional commanders, financial operatives, enforcement units, logistics and intelligence and surveillance teams. Their operatives have also been found to work to corrupt political proceedings to protect the cartels' political interests.
This method has allowed them to seize territories from their rival groups like the Sinaloa cartel.
Several members of the cartel were also said to have been killed in the operation by the Mexican Army on Sunday. The killing of the world's most wanted drug cartel leader is set to improve Mexico’s relations with the US. The country’s Ministry of Defence also said that they seized several armoured vehicles and weapons during the operation, including rocket launchers.
However, there are fears that the killing could lead to more violence in the country as rival groups may now take advantage of the blow to seize back control of territories. Mexican President Sheinbaum has critisised the strategy of taking out the "kingpin" of a cartel as it often resulted in violence. David Mora, Mexico analyst for International Crisis Group said “This might be a moment in which those other groups see that the cartel is weakened and want to seize the opportunity for them to expand control and to gain control over Cartel Jalisco in those states.”
