The U.S. State Department warned its citizens about traveling to parts of Mexico including Cancun and Playa del Carmen, as homicides rise at resorts popular with American tourists.

The advisory issued on Tuesday upgraded the warnings for two states, Quintana Roo and Baja California Sur, saying turf wars between crime gangs have led to a surge in violence. The only warning for Quintana Roo in a December statement was about lack of cellular and Internet service in some areas.

The expanded travel advisory hits at the heart of a tourism industry that brings in $20 billion a year for Mexico. The state of Quintana Roo, where the resorts of Tulum and Cozumel are also located, gets 10 million tourists a year, a third of the national total. The warnings come as homicides in Mexico are set to rise to their highest since at least the turn of the century. Quintana Roo alone has seen 169 murders this year.

“Shooting incidents, in which innocent bystanders have been injured or killed, have occurred” in both states, the U.S. warned. “While most of these homicides appeared to be targeted criminal organization assassinations, turf battles between criminal groups have resulted in violent crime in areas frequented by U.S. citizens.”

While Quintana Roo’s advisory is now stricter, it isn’t included among the most dangerous spots in Mexico, where U.S. government personnel are told to defer non-essential travel. That restriction is reserved for parts of Chihuahua, Coahuila and Colima states, among others. U.S. travel warnings of differing levels exist for most Mexican states.

Business group Coparmex, which represents more than 200 hotels, restaurants and other companies in Cancun, said the advisory will likely affect bookings this winter, when Americans head to the beaches. Adrian Lopez Sanchez, who heads Coparmex in Cancun, says security is beginning to improve after deteriorating earlier this year and last year.

Quintana Roo’s Tourism Ministry was quick to respond to the advisory, issuing a statement to say travelers to the state are “safe and protected” and the government will keep collaborating with federal and U.S. officials on security.

Hotel occupancy in Cancun, Playa del Carmen and surrounding resorts rose to 78.6 percent in the year through July from 75.1 percent in the year-earlier period, according to STR, a provider of data and analytics on the lodging industry.

In January, Asur, the airport operator that services Cancun, saw its stock slump after five people were gunned down at the Blue Parrot nightclub during an electronic music festival in nearby Playa del Carmen. The airport’s stock rose slightly to 361.20 pesos per share at close of market Tuesday. More recently, in early July, one person died after a shootout at a club right across the street from the Blue Parrot.

“Tourism is very sensitive,” Coparmex’s Lopez Sanchez said. “Warnings directed toward the U.S. market are significant.”

This article was written by Nacha Cattan from Bloomberg and was legally licensed through the NewsCred publisher network. Please direct all licensing questions to [email protected].

Photo Credit: The U.S. State Department warned its citizens about traveling to parts of Mexico, including Cancun and Playa del Carmen, as homicides rise at resorts popular with American tourists. Associated Press