The bones were found during 10 days of searching on public and private property in 11 municipalities in Coahuila state, Mexican newspaper El Siglo de Torreon reported this past weekend. The searches were conducted based on tips to authorities, the newspaper said.
While more than 500 bones were recovered, it wasn't clear how many individuals the remains represented and it was expected to take months to identify them, authorities said.
State Attorney Arreola Juan Jose Yanez said most of the remains were intact but some were burned in an apparent attempt to obscure the victims' identities. Large vats used to dissolve bodies also were found.
The Latin Times reported the remains were likely victims of drug cartels operating in the state.
The Times said the announcement of the discovery of the remains came a week after authorities in the central state of Morelos said they found the bodies of three people, and 19 bodies were found in a mass grave and four decapitated heads were left in a public square in the southwestern state of Michoacan.