Authorities had discovered 20 bodies near the frontier, close to the city of Nuevo Laredo in the state of Tamaulipas. Seventeen of the bodies had been burned, an official explained.
Five burned vehicles were also found near the bodies in the town of Miguel Aleman, across the Rio Grande from Texas in the northern state of Tamaulipas, the official said in a statement, without providing details.
Hundreds of bodies in unmarked graves have been found in recent years in the aftermath of the decade-long drug war led by the military to battle the cartels, which led to increasingly bloody turf wars.
More than 10 years after the Mexican government launched a U.S.-backed war on drug-running cartels in 2006, the country remains riddled by corruption and violence. As troops were deployed to the streets and more aggressive tactics adopted, multiple major cartel leaders were killed or captured.
But these apparent successes merely unleashed a new wave of violence as large gangs fractured, pitting factions against one another in a vicious battle for territorial control and lucrative criminal enterprises. An estimated 150,000 people have been killed in gang-related violence since 2006, according to Congressional Research Service.
The homicide rate hit a new record high in 2017 with almost 29,000 people murdered nationwide, but 2018 may well have broken that record. In the first six months of last year, homicide numbers were up 16 percent in the same period in 2017.
According to Amnesty International, up to 20,000 migrants are kidnapped every year by criminal gangs as they make their way to the U.S. Trafficking can earn the gangs as much as $50 million each year, the Mexican National Human Rights Commission has said.