MEXICO CITY — The Mexican police found nine bodies hanging from an overpass Thursday alongside a drug cartel banner threatening rivals, and seven more corpses hacked up and dumped by the road nearby. Just down the road were three more bodies, for a total of 19.

The killing spree reported by prosecutors in the western state of Michoacan was a return to the grisly massacres carried out by drug cartels at the height of Mexico’s 2006-2012 drug war, when piles of bodies were dumped on roadways as a message to the authorities and rival gangs.

Two of the bodies hung by ropes from the overpass by their necks, half naked, were women, as was one of the dismembered bodies found in the city of Uruapan, the Michoacan attorney general, Adrián López Solís, said at a news conference.

The victims had been shot to death. Some were hung with their hands bound, some with their pants pulled down.