If I read it right, it said beware if you drive dark trucks or SUVs, they want those for their drug running operations. It's reported they mostly bump you off the road, and force you to give up the vehicle. They usually don't molest you, but leave you stranded. Sometimes it's no so lucky for folks, seldom. This happens mostly at night, in off the beaten places. Most US citizen murders seem to involve drugs, 120 total last year across the entire country, some info pasted below..
As far as Nogales, it said going by day was fairly safe, fairly safe is the key. Said stay to the main toll roads, and Nogales was the safest. We drove it last year, during the day, and their hwy patrol were out looking for speeders, and checkpoints were set up.
Here is some of the initial warning/
MEXICO - General Conditions:
Millions of U.S. citizens safely visit Mexico each year for study, tourism, and business, including more than 150,000 who cross the border every day. The Mexican government makes a considerable effort to protect U.S. citizens and other visitors to major tourist destinations, and there is no evidence that Transnational Criminal Organizations (TCOs) have targeted U.S. visitors and residents based on their nationality. Resort areas and tourist destinations in Mexico generally do not see the levels of drug-related violence and crime reported in the border region and in areas along major trafficking routes.
Nevertheless, U.S. travelers should be aware that the Mexican government has been engaged in an extensive effort to counter TCOs which engage in narcotics trafficking and other unlawful activities throughout Mexico. The TCOs themselves are engaged in a violent struggle to control drug trafficking routes and other criminal activity. As a result, crime and violence are serious problems throughout the country and can occur anywhere. U.S. citizens have fallen victim to TCO activity, including homicide, gun battles, kidnapping, carjacking and highway robbery.
According to the most recent homicide figures published by the Mexican government, 47,515 people were killed in narcotics-related violence in Mexico between December 1, 2006 and September 30, 2011, with 12,903 narcotics-related homicides in the first nine months of 2011 alone. While most of those killed in narcotics-related violence have been members of TCOs, innocent persons have also been killed. The number of U.S. citizens reported to the Department of State as murdered in Mexico increased from 35 in 2007 to 120 in 2011.
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