Death of cartel boss El Mencho could impact America's ongoing fentanyl crisis as his organization allegedly caused hundreds of thousands of overdoses.

The Secretary General of National Defense, General Ricardo Trevilla Trejo, informed that Nemesio Oseguera Cervantes, alias “El Mencho”, was located thanks to a meeting he had in Tapalpa, Jalisco, with his romantic partner, who is apparently Guadalupe Moreno Carrillo.

Mexican authorities say surveillance of a romantic partner helps special forces find and kill cartel boss Nemesio “El Mencho” Oseguera Cervantes

Documents reveal the fall of “El Mencho" was the culmination of an aggressive “total elimination" strategy pursued by the U.S. against the Jalisco New Generation Cartel (CJNG).

El Mencho or Nemesio Oseguera, the leader of the feared Jalisco New Generation Cartel (CJNG) was killed in a military operation after a tip from his girlfriend.

Times reporters visiting Tapalpa found a serene town in shock after Sunday’s raid on its outskirts left dozens dead and people fleeing. And, surprisingly, no police or military presence where the battle took place.

Nemesio Rubén Oseguera Cervantes, known as "El Mencho," was arrested in the US multiple times before rising to lead the CJNG cartel.

Mexican officials said that about 80% of the recovered weapons in crime scenes were purchased in the United States and smuggled across the border.