US State Department Urges Americans to Exercise Caution Near Mexico Border City
The department said it is 'alerting U.S. citizens of this threat and change in posture.'

TL;DR
- U.S. Embassy in Mexico issued a warning on Sept. 6 about an unspecified threat in Nogales.
- U.S. government activities in Nogales, Mexico, restricted to essential daylight movement.
- Sonora is designated as a Level 3 on the U.S. Travel Advisory.
- Americans urged to exercise increased caution and be aware of their surroundings in Nogales.