A journalist from Mexico City working to expose the inner workings of a local cartel is the target of increasing death threats. The warnings come at a time when Mexico continues to be a hotspot for murdering reporters.

The criminal organization commonly known as Cartel de Tlahuac is working to silence Héctor de Mauleón, one of the founders of La Crónica de Hoy and a columnist for El Universal. The threats began last September and increased in frequency since June when he reported on an extremely violent drug trafficking gang in the Mexico City suburb of Tlahuac, La Crónica reported.

Some of the threats were sent through tweets and video messages on other social media platforms. In one of the most recent warnings, Cartel de Tlahuac used a video to issue a direct threat.

“Mr. Mauleón, you have been told to be quiet, Mr. Salgado has ordered your execution.” The video concluded with a cryptic warning: “Remember that the hand sees all.”

It is believed the recording alludes to Tlahuac’s Mayor Rigoberto Salgado Vázquez, who was connected to the Tlahuac drug gang by Mauleón’s reporting. Mauleón received other threats via email to include one that mentioned he was being watched and the sender was tasked with murdering him. Another video posted on Twitter showed a man aiming a gun at a photo of Mauleón, taking several shots at it. Two messages appeared on the screen: “El Gallo (the rooster) has his eyes on the boss,” and “You are dead, dog.” In another graphic message, Mauleón was warned: “Mr. Héctor, the sentence is about to be fulfilled, death has come for you.”

Mauleón became the target of threats when he began to report on the Tláhuac Cartel and their activities in La Condesa neighborhood of Cuauhtémoc. His dispatches described the group’s method of setting up street-level sales operations and how they were involved in taking over an apartment building, controlling criminal activities in the area.

The threats against Mauleón come at a time when Mexico is seeing a spike in the assassinations of journalists. During a six-month span, gunmen murdered 10 in Mexico–their deaths remain unsolved, Breitbart Texas reported. The most recent homicide took place in August when unknown gunmen shot local newspaper reported Candido Rios Vasquez. The veteran journalist was enrolled in a government protection program at the time of his death.

The Tláhuac Cartel was originally led by Felipe de Jesús “El Ojos” Pérez Luna, who was killed during a military operation in the Zapotitlan neighborhood, Breitbart Texas reported. Mexican security forces were met with heavy gunfire. El Ojos was later killed along with seven of his gunmen.

Robert Arce is a retired Phoenix Police detective with extensive experience working Mexican organized crime and street gangs. Arce has worked in the Balkans, Iraq, Haiti, and recently completed a three-year assignment in Monterrey, Mexico, working out of the Consulate for the United States Department of State, International Narcotics and Law Enforcement Program, where he was the Regional Program Manager for Northeast Mexico (Coahuila, Tamaulipas, Nuevo Leon, Durango, San Luis Potosi, Zacatecas.)