A new front was opened in the simmering war between Mexico's drug cartels when armed men stormed a restaurant in the Pacific resort town of Puerto Vallarta and kidnapped six men, including one who has a notorious father.
Authorities say Jesus Alfredo Guzman Salazar, son of imprisoned drug lord Joaquin "El Chapo" Guzman, was abducted in the early hours of Monday by the Cartel Jalisco Nueva Generacion (CJNG), a violent crime group that emerged six years ago in the western state of Jalisco. CJNG is currently warring with the powerful Sinaloa Cartel, led by the elder Guzman.
"Our investigation quickly identified some of those who perpetrated this action, and their links confirm that they are part of this criminal group," Jalisco state prosecutor Eduardo Almaguer said.
Guzman's son and other members of the Sinaloa Cartel were celebrating a birthday at La Leche restaurant in Puerto Vallarta. Nobody suspected an attack by a rival organization - Almaguer said Guzman Salazar and his companions were unarmed when they were forced from the restaurant.
"We found ammo for one weapon, but during the investigation of the vehicles [used in the kidnapping] we didn't find any weapons. None of the diners had or used a weapon," he told reporters.
The kidnapping is part of a war between the cartels for control of drug trafficking routes, according to Almaguer.
But the CJNG and the Sinaloa Cartel have a complex history that goes beyond drug turf.
Born out of the breakup of the Milenio Cartel, the CJNG emerged as the military arm of the Sinaloa Cartel as the pair allied in their fight against another cartel, Los Zetas.
That alliance ruptured a few years ago, and the CJNG is now expanding its territory, especially in Mexico's south-east and south-west.
Cartel observers agree El Chapo's capture in January after his escape last year from prison likely emboldened the CJNG, leading to the kidnapping of the kingpin's son.
The kidnappings are a major blow not only to the Guzman family but to his entire criminal network. The CJNG's offensive can be considered a major slap in the face of its old ally.
In the absence of El Chapo, who is imprisoned and fighting extradition to the United States, Mexican and American authorities say Guzman Salazar and his brother Ivan Archivaldo Guzman, better known as "Chapito," are among those leading the Sinaloa cartel.
Almaguer said investigators have no evidence to support rumours that Chapito was also abducted from the restaurant.
Some experts believe that when coupled with previous events, the abduction demonstrates the dwindling power of the Sinaloa Cartel.
In June there were reports of an armed confrontation between groups near El Chapo's hometown, Badiraguato, in the mountains of the north-west state of Sinaloa. Armed gunmen looted the home of the kingpin's mother.
That attack was perpetrated not by the CJNG but another organization battling for control of the Sinaloa Cartel's territory - another reflection of the cartel's weakness.
The kidnapped and the kidnappers are being actively sought by police. Almaguer said there had as yet been no demands for ransom.
The Mexican attorney general's office has become involved in the case, saying it will take "the necessary steps to clarify the facts that are under federal jurisdiction."
What will the Sinaloa Cartel do next? Mexican media is speculating that negotiations to secure the release of Guzman Salazar and the five other members could be underway, which would partly explain the organization's inactivity.
Negotiations or not, El Chapo's cartel is expected to respond, with the final outcome likely to be acted out like most cartel conflicts - with a bloody finale.