19 bodies were suspected victims of a dispute between drug cartel groups found, Mexican police said in a statement.
Nine bodies were found hung under the bridge, and seven others were mutilated.
While three other bodies were dumped not far from the site of the massacre.
The discovery of 19 bodies occurred in the city of Uruapan, Michoacan state, West Mexico, on Thursday.
Among the mutilated victims there was at least one woman, according to a police report.
Near the body hung under the bridge a banner with the initials of the drug cartel was found.
The banner contained a message writing, “Be a patriot, kill Viagra”, which is believed to refer to a rival cartel group, Viagras.
“At the end of the road from where seven mutilated bodies were found, three other bodies were found. Thus there were a total of 19 bodies in a terrible dispute,” the authorities said.
Chief State Prosecutor Michoacan, Adrian Lopez, said that there was a war between different drug cartel criminals.
“They are fighting for territory over the production, distribution and consumption of drugs”, Lopez said.
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