On Oct. 19, 2021, Armando Linares López was writing up notes from an interview when his cellphone buzzed with an unknown number. Linares, 49 and stocky with black hair that was just starting to show gray streaks, ran an online news site in a small Mexican city called Zitácuaro. He knew his beat so intimately that calls from unfamiliar phone numbers were rare.

But the man on the other end spoke in a way that was instantly familiar. Linares had come to know that pitched, menacing tone from years of run-ins with every kind of Mexican gangster.

“This is Commander Eagle,” the voice said. “I’m from the Jalisco New Generation Cartel.”

Zitácuaro, in the hills of the state of Michoacán, had for years mostly been known for its fertile avocado orchards and the pine-oak forest where tourists came to see the annual arrival of the monarch butterflies. But its central location had made it increasingly attractive to the drug trade. Farmers grew marijuana and opium poppy, the source of heroin, in nearby mountains, and in recent years international drug cartels had been using Michoacán as a way station for methamphetamine and fentanyl shipments. Linares’s rise as a journalist coincided with the drug boom, and he watched its devastating effects on Zitácuaro: severed heads dumped in front of a car dealership, business owners kidnapped for ransom and a government that seemed unwilling or unable to do anything about it.

This story was recorded by Audm. To hear more audio stories from publications like The New York Times, download Audm for iPhone or Android.

Unlock full access to New York Times podcasts and explore everything from politics to pop culture. Subscribe today at nytimes.com/podcasts or on Apple Podcasts and Spotify.