The dismembered bodies of at least 14 people have been found in an abandoned pickup vehicle in the eastern Mexican state of Veracruz, authorities say.
Veracruz is the scene of a violent drug turf war.
Alerted by an anonymous call late on Monday, authorities found the vehicle parked on a road in the town of Tuxpan near the border with the state of Tamaulipas, the state prosecutor's office said on Tuesday.
Local media quoted witnesses as saying the victims were mostly men in their 20s whose dismembered body parts had been stuffed into bags.
A message found at the site suggested the killings were linked to strife within the Zetas drug gang, created by elite anti-drug commandos who deserted and went to work for the Gulf cartel in the mid-1990s as hired guns.
They later split to form their own cartel.
The northern border state of Tamaulipas is a stronghold of the Zetas, who been locked in conflict with both the Sinaloa cartel and the Gulf cartel.
The discovery of the bodies reflects a growing trend - the numbers of homicides of this nature have risen sharply since early 2011, with bodies often dumped in public places.
On June 7, 14 dismembered bodies were found in an abandoned vehicle, which was illegally parked near city hall in Ciudad Mante in northeastern Mexico.
On May 4, 14 mutilated bodies were discovered in the Tamaulipas city of Nuevo Laredo, on the border with Laredo, Texas.
Earlier that day, nine bodies had been found hanging from an overpass in Nuevo Laredo.
Nuevo Laredo and the roads leading to the border town are key smuggling routes, as 40 per cent of all cargo crossing northbound into the US from Mexico goes through the city.
Last September, 35 bodies were left dumped in lorries in broad daylight in a heavily used road in the port of Veracruz, just before the start of a conference of prosecutors from around the country.