They are believed to have been buried between ten and 14 years ago, according to local authorities. The state of Tamaulipas, where the bodies were found, has long been plagued by organized crime.
More than 110,000 disappearances have been registered in Mexico since 1962. Criminal gangs are believed to be behind the majority of them. In Tamaulipas alone, 13,000 people are missing.
Over 350,000 murders have been recorded in the country since late 2006, when the military became involved in what was described as a war on drugs.