MEXICO CITY (AP) — A commando of drug gang gunmen on Thursday stormed ashore at a beach on Mexico’s Caribbean coast and executed two drug dealers from a rival gang.

The dramatic shooting attack sent tourists scrambling for cover at the resort of Puerto Morelos, just south of Cancun.

The two suspected drug dealers killed Thursday had apparently arrived at the beach in front of the Azul Beach Resort and the Hyatt Ziva Riviera Cancun earlier in the day, claiming it was now their territory.

“About 15 people arrived on the beach to assassinate two men who had showed up saying they were the new dealers in the area,” the head prosecutor of Quintana Roo state, Oscar Montes de Oca, told the Radio Formula station.

Montes de Oca’s office said earlier in a statement that “there was a clash between rival groups of drug dealers on a beach” near the hotels. Several cartels are fighting for the area’s lucrative retail drug trade, including the Jalisco cartel and the a gang allied with the Gulf cartel.

Montes de Oca said one of the men targeted in the attack fled into one of the hotels before dying. The other was killed on the beach. He also said one person suffered non-life-threatening injuries in the attack, but authorities could not determine whether that person was a hotel employee or a guest because they were still undergoing medical treatment.

Gov. Carlos Joaquin said the commando wore ski masks and arrived by boat at the beach. Montes de Oca said they fled in a boat after the attack.

Joaquin called the attack “a serious blow to the development and security of the state … putting the image of the state at grave risk.”

Guests at the Hyatt Ziva Riviera Cancun posted videos and photos of tourists hiding or nervously milling in the lobby and hallways of hotels during the incident.

Guests at the nearby Azul Beach Resort also posted videos of people taking shelter or gathering in the lobby. An employee who answered the phone at the hotel said the shooting occurred on the beach near the facility.

Mike Sington, a guest at the Hyatt Ziva Riviera Cancun, wrote in his Twitter account that “Guests are telling me they were playing volleyball on the beach, gunman approached firing gun. Everyone ran from beach and swimming pools. Staff hustled us into hidden rooms behind the kitchens.”

Sington tweeted “I’ve never been so scared, literally shaking,” before adding “I’m fine now, barricaded in my hotel room for the night, just trying to decompress.”

The Puerto Morelos shooting comes two weeks after a California travel blogger and a German tourist were killed in a similar shootout in the beach town of Tulum.

A San Jose, California woman born in India, Anjali Ryot, and German citizen Jennifer Henzold were apparently hit by crossfire from the Oct. 20 drug dealers’ shootout in Tulum, south of Puerto Morelos.

Three other foreign tourists were wounded in the shooting at a street-side eatery that has some outdoor tables, right off Tulum’s main strip. They included two German men and a Dutch woman.

The German Foreign Office issued a travel advisory about the violence, advising its citizens “if you are currently in the Tulum or Playa del Carmen area, do not leave your secured hotel facilities.”

The Tulum gunfight also apparently broke out between two groups that operate street-level drug sales in the area, according to prosecutors.

The administration of President Andres Manuel Lopez Obrador has pinned its hopes on the so-called Maya Riviera, where it has announced plans to build an international airport and a stop for the Maya train, which will run in a loop around the Yucatan peninsula.