The US State Department warns of crime and kidnapping throughout the country.
"Violent crime, such as homicide, kidnapping, carjacking, and robbery, is widespread," the advisory reads. "The US government has limited ability to provide emergency services to US citizens in many areas of Mexico as travel by US government employees to these areas is prohibited or significantly restricted."
The government recommends Americans don't travel to the states of Colima, Guerrero, Michoacan, Sinaloa, and Tamaulipas.
The advisory warns that Tamaulipas state is particularly dangerous:
"Violent crime, such as murder, armed robbery, carjacking, kidnapping, extortion, and sexual assault, is common. Gang activity, including gun battles and blockades, is widespread. Armed criminal groups target public and private passenger buses as well as private automobiles traveling through Tamaulipas, often taking passengers hostage and demanding ransom payments. Federal and state security forces have limited capability to respond to violence in many parts of the state."