CHICAGO (WLS) — On Sunday, the Mexican military succeeded in eliminating Nemesio Rubén Oseguera Cervantes, known as “El Mencho,” who was the head of the Jalisco New Generation Cartel. This significant event dismantled the leadership of Mexico’s most formidable drug cartel, sending shockwaves throughout the country.

Back in 2018, the ABC7 I-Team highlighted that “El Mencho” was the primary target for the DEA. Within the law enforcement community, he was deemed Chicago’s most sought-after fugitive and labeled as “Public Enemy Number One.”

While no U.S. troops were directly involved in the ground operation against the notorious cartel leader, ABC News revealed on Sunday night that American forces did provide crucial intelligence support, although the specifics of this assistance remain undisclosed.

ABC7 received updates from Chicago-area residents currently in Mexico, who described the widespread uncertainty as violent conflicts erupted in various regions.

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Scenes of dark smoke clouds were visible Sunday, disrupting the usually serene western coastline of Mexico. Burned-out buses were left abandoned on the roads, while helicopters flew over the tourist hotspot of Puerto Vallarta.

“There are blockades, cars set ablaze, and buses obstructing the roads. So, no one can take an Uber, a taxi, or a bus. Everything is at a standstill,” reported David Miranda from Pilsen.

Miranda, his cousin and friends were vacationing in Puerto Vallarta. They are now stranded following violent clashes that erupted after the cartel leader’s death.

“It’s a way of showing their presence or their power,” said Dr. Emilio Kouri, director of the Katz Center of Mexican Studies at the University of Chicago. “And most of all, I think their defiance in a moment that is quite perilous in terms of not knowing what may come next.”

Miranda says as he and his group waited for a ride share that never came, they heard from nearby hotel employee.

“She says, if you love yourself and you love your life, do not try to even make it to the airport,” Miranda said.

Jim Murphy from Joliet, also stranded in Puerto Vallarta, shared an image of a building that burned just block away from where’s he’s sheltering in place.

“The United States State Department has issued a shelter in place warning to all U.S. citizens in Mexico right now,” Murphy said. “The governor of the state of Jalisco has done the same as has the mayor of Puerto Vallarta.”

International airlines have cancelled flights in Puerto Vallarta and Guadalajara, temporarily stranding tourists like Miranda.

“We don’t know how we’re going to get food, because it’s Airbnbs,” Miranda said. “So everything is closed, the corner stores, everything is closed.”

Dr. Kouri says “El Mencho’s” death could shake up one of Mexico’s most violent cartels and is significant for the country and U.S.-Mexico relations.

“This is something that is already being warmly welcomed by the U.S. government and that will help strengthen the idea that Mexico’s government is active in trying to limit the power of these organizations,” Dr. Kouri said.

Several airlines continued to suspend services as of Sunday night, and there was no official timeline on when normal flight operations would resume.

It’s a waiting game for people, including the Chicago-area travelers, to get home, safely.