The U.S. has issued “do not travel” advisories for five Mexican states denoting the highest level of possible danger for travelers.
The State Department unveiled its updated assessments of the group Wednesday, ranking them the same as war-torn nations like Somalia, Syria and Yemen.
The U.S. now lists Tamaulipas, a Mexican state that shares a border with Texas, as an area of greatest risk to potential travelers.
American also now assigns the same status to Colima, Guerrero, Michoacan and Sinaloa along the Pacific coast.
The five states are all notorious for drug cartel activity, including either vast cultivation of drug crops or hosting narcotics trafficking routes.
The State Department’s has previously discouraged travel to some or all parts of the group, but Wednesday’s Level 4 warning marks its most cautionary designation yet.
The agency assigned another 11 Mexican states Level 3 status Wednesday, which pressures Americans to “reconsider travel” there.
Mexico has 31 states, half of which are now under Level 4 or 3 warnings, and the nation has a Level 2 ranking overall.
The State Department’s Level 2 status means Americans should “exercise increased caution” due to concerns about crime.
Tamaulipas has long suffered from territorial struggles between rival drug gangs, and Sinaloa is home to the cartel bearing the same name.
Michoacan was so dominated by a drug cartel in 2013 that vigilantes took up arms to drive them out.
The State Department last year extended a total ban on personal travel by U.S. government personnel to Guerrero.
Colima now has Mexico’s highest homicide rate, with 83.3 killings per 100,000 residents, according to figures for the first 11 months of 2017.
The growth of the Jalisco New Generation drug cartel in Colima has caused the homicide rate there to skyrocket in recent years.
The State Department lists most of northern Mexico – including four of the country’s border states with the U.S. – under Level 3 advisories.
The Associated Press contributed to this report.