Six of the bodies found Tuesday in the city along the US border were inside barrels with sulphuric acid in the city centre, while the two others were found in the suburbs.
The public prosecutor’s office in the state of Baja California said the barrels included a message.
“This is what happens to the engineer, and we will make stew with all those who are with him,” the message said.
The two other bodies were wrapped in blankets which had the message, “here are your people, Duarte.”
The authorities did not immediately know the identity of the two people mentioned specifically in the notes.
The bodies were found after anonymous calls were received by the police.
On Monday, 16 bodies were found in two vacant lots. Some of them were half-naked, with bound hands or feet, and showed signs of torture. They had been killed just a few hours earlier, and at least seven of them had their tongues severed.
On September 12, 24 people were found dead just outside Mexico City.
According to media reports, more than 3,300 people have been killed so far this year in Mexico in actions related to organized crime, despite a far-reaching military and police operation that has been in place to combat drug gangs since late 2006. (dpa)