A second monarch butterfly advocate has been found dead in Mexico, just days after another prominent activist’s body was discovered in a well — sparking fears from conservationists that the two deaths are linked, according to a new report.

Raúl Hernández, a tour guide at a monarch butterfly sanctuary in Michoacán state, vanished Monday, Jan. 27, the BBC reported. His body turned up Sunday on top of a hill in the El Campanario sanctuary.

Forensic experts said Hernández had a deep wound to his head and his body was covered in bruises, according to the report. Before his disappearance, Hernandez had left work as usual and was reportedly last seen in the village of El Oyamel.

Authorities are probing his death, as local rights groups worry it may be linked to that of Homero Gómez González, who disappeared in the same region Jan. 13.

González’s body was found two weeks later floating in a well, not far from the El Rosario Monarch Butterfly Preserve he managed.

Investigators initially said González’s body showed no obvious signs of trauma, but it was later revealed he had suffered a blow to the head before drowning in the well, the BBC reported, citing autopsy results.

Conservationists immediately suspected that angry loggers or criminal groups in the town of Ocampo in Michoacán state — known for its violent gangs — may have targeted González, who was known as Mexico’s most prominent butterfly activist, according to reports at the time.

González’s family told local media an organized crime gang had previously threatened the well-known activist.

González opened his sanctuary in November in an effort to stop illegal logging in the area — a key habitat for monarch butterflies, according to the report.

The Mexican government has outlawed logging in the region, allowing the monarchs to flourish — but the move has fueled tensions between local loggers and conservationists.