Mexican officials in the central state of Guanajuato say seven bodies have been found in the city of Salamanca and they appear to be members of a criminal organisation.
Four others were found dismembered in multiple black plastic bags in two separate locations, on the side of a highway and in a neighborhood.
Written messages from a rival gang were found next to the bags. An agency spokesman declined to name the alleged criminal groups, but said they sell drugs and stolen gasoline.
Mexican state oil company Pemex operates a refinery in Salamanca. The town has become a hotbed for fuel theft in recent years, with criminal gangs allegedly pressuring refinery workers to help them steal gasoline.
Local media reported Wednesday that federal police and the army conducted a surprise sweep at the refinery, searching workers and their vehicles.
A spokesman for the federal police said he was unable to immediately confirm the raid or whether any arrests were made.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)