(CNN) -- Twelve to 15 bodies showing signs of torture were found on the side of a remote highway in the Mexican state of Michoacan, the state attorney general's office told CNN en Español.
Authorities were still arriving at the scene Monday evening to verify the exact body count, officials said.
The discovery follows coordinated attacks in at least eight cities in Michoacan that killed three federal police officers and two soldiers Saturday in what officials called an unprecedented onslaught by drug gangs.
The bodies found Monday were in the same place where four bodies showing signs of torture were dumped in June, the Universal newspaper reported.
Michoacan state is on the Pacific coast of Mexico.
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