Police found the mummified bodies of two women and three men Wednesday stuffed in plastic bags in a pickup truck left near a highway in the northern Mexico state of Chihuahua, AP reported.
State police said the bodies - apparently mummified by the desert climate - had not been identified.
The site where the truck was found is south of the violence-plagued border city of Ciudad Juarez, where the truck had been reported stolen.
University authorities in Ciudad Juarez also reported Wednesday that a freshman had been found dead, wrapped in a blanket at a local fairground.
Mexico was shocked when two university students in Monterrey were killed in the crossfire of a shootout between soldiers and gunmen in March.
Also Wednesday, authorities said about 88 tons (80 metric tons) of a precursor chemical used to make methamphetamines had been seized at the Pacific Coast seaport of Manzanillo.
The chemical ethyl phenyl acetate, also known as phenylacetic acid, can also be used in cocaine processing.
The navy said the chemical was found in five shipping containers sent from China to Manzanillo.
Drug traffickers have turned to phenylacetic acid since Mexico effectively banned imports of another precursor, pseudoephedrine.
A similar confiscation, reported at the time as the largest single seizure of its type, was reported by authorities at the same port earlier this month.