The U.S. has issued a travel warning for Cancun and other parts of Mexico due to growing violence in these regions.

The recent wave of danger

that has marked the states of Quintana Roo and Baja California Sur — where the U.S. State Department has upgraded the severity of its warnings — is caused by gang-related violence.

There has reportedly been a criminal war marked by turf battles between two organized groups. While the conflict mainly involves two gangs, innocent bystanders have been shot and met with other violent fates as a result of being in the wrong place at the wrong time.

Drugs are believed to be a part of the conflict between these criminal groups and they have been for years, but violence has surged in 2017. Downtown Cancun is a popular tourist destination among Americans, and back in January there were five people who were killed at a nightclub in Playa del Carmen, which was nearby.

The tourism industry makes up about 7% of Mexico’s gross domestic product, raking in more than $20 billion a year. Part of the increase in violence could be the result of the growth in tourism developments in Los Cabos.

The popular destination has grown at an incredible rate over the last two years, bringing in migrants who have built hotels and resorts in the area.

Additionally, the opioid crisis in the U.S. has resulted in higher demand for heroin from Mexico, which has caused power struggles between the nation’s top cartels.