The graves were discovered in the municipality of San Fernando in the border state in April. Many of the bodies are thought to be people abducted from buses traveling through the region.
As the Brownsville Herald reports, authorities refused to divulge the name of the Americans or the circumstances in which they were abducted. However, the consul-general’s office in Matamoros had received reports of Americans being pulled off inter-city buses in the area.
While just 111 Americans (out of an estimated one million resident in Mexico) were killed in 2010, a series of high-profile crimes has increased worries about the safety of travel south of the Rio Grande. In one of the more notorious incidents, a consular employee and her husband were killed in a drive-by shooting in Juarez in March 2010.
The mass graves in Tamaulipas, along with the near-simultaneous discovery of an even larger network of clandestine graves in Durango, rattled a nation long accustomed to drug atrocities. The Tamaulipas killings have been blamed on the Zetas, while in Durango authorities believe the bodies may be the victims of fighting between rival factions of the Sinaloa Cartel.
An alleged Zeta operative told the Houston Chronicle this week that the group had made a habit of abducting bus passengers and forcing them to fight to the death, apparently for the gangsters’ amusement.