15 bodies were found piled up in the middle of the Matamoros -Ciudad Victoria highway in the town of St. Germain near San Fernando, Tamaulipas.
Among those executed were two women who like the rest of the bodies showed signs of torture, with their hands tied behind their back and blindfolded.
All presented gunshot wounds in various parts of the body and two of them were completely naked.
Crime scene investigators testified to several spent casings found scattered around the bodies.
The bodies were transported to Matamoros and guarded by units of the Federal Police and the Mexican Army.