The United States said Thursday that it has extended its decision authorizing the families of US diplomats and others working in violence-hit northern Mexico to live back in the United States.
The State Department said "the authorized departure of family members" of US government personnel from US consulates in "Tijuana, Nogales, Ciudad Juarez, Nuevo Laredo, Monterrey and Matamoros has been extended."
The State Department statement was an update of an April 12 decision authorizing extended departures.
On March 14 the State Department authorized the departures of family members after a US employee of the US consulate in the city of Ciudad Juarez, her US husband and a Mexico consular employee were murdered.
Much of the country's drug-related violence has occurred in the northern border region, it said, pointing out particular areas that US travelers should avoid.
"US citizens should defer non-essential travel to Ciudad Juarez and to the Guadalupe Bravo area southeast of Ciudad Juarez," it said.
"US citizens should also defer travel to the northwest quarter of the state of Chihuahua, including the city of Nuevas Casas Grandes and surrounding communities," it added.
The statement also said "large firefights" involving drug gangs have occurred mostly in northern Mexico, including Ciudad Juarez, Tijuana, Chihuahua City, Nogales, Nuevo Laredo, Piedras Negras, Reynosa, Matamoros and the industrial city of Monterrey.
"The situation in northern Mexico remains fluid; the location and timing of future armed engagements cannot be predicted," it said.
"US citizens are urged to exercise extreme caution when traveling throughout the region, particularly in those areas specifically mentioned in this travel warning," the statement said.