At least 73 people died in the attempt to capture a Mexican cartel leader and its violent aftermath

Nemesio Oseguera Cervantes, called "El Mencho," was the boss of one of the fastest-growing criminal networks in Mexico, known for trafficking fentanyl, methamphetamine and cocaine to the United States and staging brazen attacks against Mexican government officials. The organization responded to his death with widespread violence, including blocking roads and setting fire to vehicles.

Oseguera Cervantes died after a shootout in his home state of Jalisco as the Mexican military tried to capture him. Mexican Defense Secretary Ricardo Trevilla said Monday that authorities had followed one of Oseguera Cervantes' romantic partners to his hideout in Tapalpa.

The cartel leader and two bodyguards fled into a wooded area where they were seriously wounded in a firefight. They were taken into custody and died on the way to Mexico City, Trevilla said.

In a different location in Jalisco, soldiers also killed another high-ranking cartel member who Trevilla said was coordinating violence and offering more than $1,000 for every soldier killed.

The dead included 25 members of the Mexican National Guard who were killed in six separate attacks, Security Secretary Omar García Harfuch said.

Harfuch said some 30 criminal suspects were killed in Jalisco, and four others were killed in the neighboring state of Michoacan. Also killed were a prison guard and an agent from the state prosecutor's office.

As the threat of violence loomed, several Mexican states canceled school Monday, while local and foreign governments warned their citizens to stay inside.

President Claudia Sheinbaum urged calm, and authorities said all of the more than 250 cartel roadblocks across 20 states had been cleared by Monday.

The White House confirmed that the U.S. provided intelligence support to the operation to capture the cartel leader and applauded Mexico's army for taking down a man who was one of the most wanted criminals in both countries.

Mexico hoped the death of the world's biggest fentanyl traffickers would ease Trump administration pressure to do more against the cartels, but many people were on edge as they waited to see the powerful cartel's reaction.

Many fear more violence

The U.S. Embassy said via X that its personnel in eight cities and in Michoacan would shelter in place and work remotely Monday. It warned U.S. citizens in many parts of Mexico to do the same.

Cars began circulating in Guadalajara before sunrise Monday with the start of the workweek, a notable change from Sunday, when Jalisco's state capital and Mexico's second-largest city was almost completely shut down as fearful residents stayed home.

More than 1,000 people were stuck overnight in Guadalajara's zoo, where they slept in buses. On Monday morning, mothers wrapped in blankets carried their toddlers out of the buses for a much-needed bathroom break as police trucks guarded the area.

Luis Soto Rendón, the zoo's director, said many had been trapped there since Sunday morning, when violence broke out in Jalisco and the surrounding states. Families concluded they could not return home in nearby states like Zacatecas and Michoacan.

"We decided to let people stay inside the zoo for their safety," Soto said. "There are small children and senior citizens."

José Luis Ramírez, a 54-year-old therapist, was in a long line of people waiting outside a pharmacy, one of the few businesses that were open Monday in Guadalajara. Families were buying food, medicine, water, diapers and baby formula, from pharmacists through a chained door.

It was Ramírez's first time leaving the house since violence erupted over the weekend, but he struck a hopeful tone, saying that despite the bloodshed, civilians needed to move forward.

"We have to not think scared, but be cool-headed, like they say, and take things as they come," he said.

Traffic was light in the city, and outwardly it appeared that those who could afford to stay home were doing so, while those who had to work were carefully making their way across the city.

Irma Hernández, a 43-year-old hotel security guard in Guadalajara, arrived at work early Monday.

She normally takes public transportation to work, but buses were not running, and she had no way to cross the city. Her bosses organized a private car to pick her up. Her family, she said, was staying at home, too scared to leave.

"I am worried because I don't know how to get home if something happens," she said.

Blow against cartel welcomed by the U.S.

U.S. President Donald Trump has demanded Mexico do more to fight the smuggling of fentanyl, threatening to impose more tariffs or take unilateral military action if the country does not show results.

There were early signs that Mexico's efforts were well received by the United States.

U.S. Ambassador Ron Johnson recognized the success of the Mexican armed forces and their sacrifice in a statement late Sunday. Under the leadership of Trump and Sheinbaum, he said, "bilateral cooperation has reached unprecedented levels."

But the operation may also pave the way for more violence as rival criminal groups take advantage of the blow dealt to El Mencho's organization, said David Mora, Mexico analyst for the International Crisis Group.

"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," he said.

Ever since Sheinbaum took office, "the army has been way more confrontational, combative against criminal groups in Mexico," Mora said. "This is signaling to the U.S. that if we keep cooperating, sharing intelligence, Mexico can do it. We don't need U.S. troops on Mexican soil."

The U.S. State Department had offered a reward of up to $15 million for information leading to the arrest of El Mencho. The Jalisco New Generation Cartel, which began operating around 2009, is one of the most powerful criminal organizations in Mexico.

In February 2025, the Trump administration designated the cartel as a foreign terrorist organization. It has been one of the most aggressive cartels in its attacks on the military — including on helicopters — and is a pioneer in launching explosives from drones and installing mines.