Homero Gómez González went missing on January 13. On Wednesday, the fear of many was confirmed. Gómez’s body was found in a well near the Rosario monarch butterfly sanctuary where he worked, in Michocán, Mexico. He was 50 years old.

The cause of death is not official, according to local reports, but his body reportedly showed signs of torture, leading authorities to consider affixation by submersion as a probable cause.

“This is a very regrettable act, very painful,” President Andrés Manuel López Obrador said at a press conference on Thursday. “It’s part of what makes us apply ourselves more to guarantee peace and tranquility in the country.”

For the last decade, Gómez devoted his life to protecting the animal his grandfather once told him carried the souls of their ancestors. Gómez, who grew up in El Rosario had a connection to the beautiful, brittle creatures. “They are girlfriends of the sun and the souls of the dead. Simply the patrimony of humanity,” he said in one of his last videos.

“It’s been a fight to maintain it,” Gómez told The Washington Post just weeks before his death. “And it hasn’t been easy.”

Though he loved butterflies and the trees that housed them, Gómez grew up selling wood as a means of survival. In the early 2000s, when deforestation became an issue locally, Gómez stopped and convinced many others to as well. He would later go on to become Rosario’s mayor. Logging is now entirely illegal in the area.

“We were afraid that if we had to stop logging, it would send us all into poverty,” he said.

At least 14 environmental defenders were murdered in Mexico in 2018, according to The Guardian.

“I offer my condolences to Mr. Gómez González’s family, his colleagues and all of those who, in Mexico and elsewhere, sometimes at the risk of their lives, work every day to protect this natural heritage which is shared by all of humanity,” said Mechtild Rössler, Director of the World Heritage Center, which the Monarch Butterfly Biosphere Reserve is a part of.