Factual error: At the tunnel scene you see the "Delta" members using the single tube N.V.G. Delta has been using the standard binocular type for years now.
Factual error: The lightbars seen on the Mexican Federal Police trucks in Juárez are incorrect - they show both red and blue lights to the front, but actual MFP vehicles show only reds to the front. Also the uniform vests are in Portuguese, not Spanish - the accent is on the wrong "i."
Answer: The film was apparently offensive to at least the mayor of Juarez. According to him, the film is based somewhat on stereotypes of the region and the depiction of Juarez as a violent region controlled by drug cartels is outdated.
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