Mexican authorities will not confirm anything, but American border towns are orchestrating a plan of action.
On the streets of Rio Grande City, police have beefed up patrols and are staying in constant communication with U.S. Border Patrol, the Starr County Sheriff's Department and Customs and Border Protection.
It is unfortunate, said Asst. Chief Noe Castillo with the Rio Grande City Police Department. "But we are ready for anything and we will do whatever we have to do if it does come to this side."
The U.S. State Department has renewed its travel warning into Mexico, singling out Reynosa and Matamoros as areas of concern.
The alert stays in effect until August.
Mexican resident Anna Saenz said Tuesday that she has been commuting to the U.S. every day for the past 26 years and has never had trouble crossing the border.
"As long as I mind my business, I TMm fine. My kids don't want me to come over here, but this is my home."
Down the border in Reynosa, a banner was seen hanging from a highway on Sunday.
It read "Reynosa is a safe city and nothing will happen. The cartel does not mess with civilians so they should continue their lives as normal."
Part of that normality often involves Americans crossing into Mexico for food and medicine.
Rio Grande City Mayor Ruben Villarreal said those actions may change.
"They don't do it anymore as much and with today TMs news they are being even more cautious."
Gloria Martinez was heading to Mexico when she stopped to speak with Action 4 News.
Everything is cheaper over there. We only go when we need things.
However, Martinez decided to turn around just short of the international bridge and headed back home Tuesday.
Traveling across the border was not worth any possible risk.
Meanwhile, all Rio Grande Valley international bridges are open to traffic.