Texas Agriculture Commissioner Sid Miller sent out a warning for people to be careful near the border. 

The warning is connected to the death of a Brownsville Rancher in Mexico.

Channel 5 News spoke with a rancher who asked to keep his identity a secret for his safety. For three generations, his family has harvested sorghum in southern Rio Bravo.

The farmer says the land his farm sits on has been a battleground for opposing cartels groups. He believes they want to take control of the routes to smuggle drugs and people into the Rio Grande Valley.

Since the start of this year, he, other farmers and their families have had to be careful where they step and drive. They're watching out for an improvised explosive device, or an IED.

The farmer believes cartel violence expanded to now include explosives. He blames Mexico's previous president. He says for six years, Andrés Manuel López Obrador's administration failed to prevent violence between rival cartels.

RELATED STORY: Brownsville man speaks out after father killed in IED blast in Tamaulipas

At the end of January, the state of Tamaulipas posted a warning about IEDs on social media. A few weeks later, a Brownsville man died in a blast. His death was not related to drugs or human smuggling.

Antonio Céspedes Saldierna was in the area of Santa Rita in San Fernando, Tamaulipas. He was driving his own pickup truck on his own land when he was killed by an IED.

Former FBI agent Arturo Fontes believes cartels are matching the changing political environment. The new Trump Administration is asking Mexico to do more to keep cartels from sending drugs and migrants across the border.

"It's like squeezing a water balloon. When the Mexican or the U.S. puts pressure, the cartels, they do different things," Fontes said. "This threat of these IEDs, these drones or bombs, is not targeting Americans, Mexican citizens per-se, it's targeting cartels that are encroaching into their area."

Throughout February, Mexico's national defense secretary has been locating and deactivating explosive devices.

So far, Tamaulipas state police have located them in 11 rural communities, between Reynosa and Rio Bravo and reaching as far south as San Fernando and Valle Hermoso.

Watch the video above for the full story.