Texas advises against traveling to Mexico during spring break

Texas authorities are advising residents to avoid traveling to Mexico during spring break "due to the ongoing violence throughout that country."

The Texas Department of Public Safety issued an advisory warning against travel to the country for spring break "and beyond."

"Drug cartel violence and other criminal activity represent a significant safety threat to anyone who crosses into Mexico right now," Department of Public Safety Director Steven McCraw said in a statement on Friday. "We have a duty to inform the public about safety, travel risks and threats. Based on the volatile nature of cartel activity and the violence we are seeing there; we are urging individuals to avoid travel to Mexico at this time."

The warning was issued a week after four Americans were kidnapped shortly after crossing the border into Matamoros, Mexico, which is in the northeastern state of Tamaulipas just south of Brownsville, Texas.

Two of the Americans, including one who was traveling to the region for a cosmetic procedure, were rescued on March 7. Two others were found dead.

Five alleged Gulf Cartel members have since been charged with aggravated kidnapping and murder.

A source close to the investigation told ABC News that investigators believe the gunmen wrongly believed the kidnapped Americans were rival human traffickers who were in an area of Mexico categorized as "do not travel" by the U.S. government due to the increased risk of crime and kidnapping.

The most popular Mexican tourist destinations have been rated a level two by the State Department, where travelers are advised to "exercise increased caution" -- the same rating given to France, Germany, the U.K. and a dozen other countries.

AAA recently reported that international travel is up 30% compared to last year, and Cancun, Riviera Maya and Mexico City are listed as top spring break destinations.

Those who do decide to travel to Mexico are advised to register with the nearest U.S. Embassy or Consulate prior to their departure, Texas authorities said.

"DPS understands many people do travel to Mexico without incident, but the serious risks cannot be ignored," the agency said. "All travelers are encouraged to carefully research any planned trips and, again, consider postponing or canceling travel to Mexico at this time."