The number of bodies found dumped in mass graves in north-eastern Mexico has risen to 72, after 13 more corpses were uncovered by authorities.
Earlier, 59 bodies were discovered in eight mass graves on a ranch in the farming village of La Joya, in San Fernando municipality in Tamaulipas state.
The first discovery was made by a military patrol after a tip-off in late March about the disappearance or abduction of bus passengers in the area.
Advertisement: Story continues below
While the violent Zetas drug cartel - led by former elite Mexican commandos - is widely known to be active in the region, authorities have refused to say who may be responsible for the slaughter.
In August 2010, 72 migrants from El Salvador, Honduras, Guatemala, Ecuador and Brazil were found dead in San Fernando, killed for refusing to work for drug traffickers.
Seven major drug gangs are operating in Mexico and their bloody clashes with each other and the authorities have left over 34,600 people dead since December 2006.
