MEXICO CITY — Prosecutors in western Mexico said Tuesday that three people still appeared to be missing after a gang kidnapped some members of a group of over a dozen visitors to the Pacific resort of Puerto Vallarta earlier this month.

Jalisco state prosecutor Gerardo Octavio Solis said one member of the group of men visiting the resort from the neighboring state of Guanajuato escaped the July 18 attack, in which one of the visitors was killed by a gunshot.

The survivor said many of the abducted men had been taken to a house in Puerto Vallarta, held there and most were later released. The survivor said it appeared three of the kidnapped men could still be in the custody of their captors.

Solis said the mass kidnapping "was an attack directed at three or four people" in the group, who had been touring the area in ATVs and SUVs.

Apparently tourists, there had been no previous explanation why the gunmen might attack the group. Local media have widely pinned the attack on the Jalisco New General Cartel, which is active in Puerto Vallarta.

Solis seemed to suggest, without stating it, that the attack may have involved gang rivalries, though the victims have largely been described as businessmen.

He said the man who was killed once had registered addresses in the Guanajuato hamlet of Santa Rosa de Lima, the home turf of a gang of the same name. The Jalisco cartel and the Santa Rosa de Lima gang have been fighting a bloody turf battle for control of Guanajuato that has made it the deadliest state in Mexico.

Solis said some of the dead man's relatives had criminal backgrounds.

The Puerto Vallarta attack initially recalled memories of the 2011 kidnapping of 20 vacationing men from Michoacan state in the Pacific coast resort of Acapulco. Authorities believed those tourists were mistaken by drug traffickers for members of the Michoacan-based La Familia cartel. Some of the men's decomposed bodies were later found in a mass grave.

On Saturday, Solis had said 13 or 14 people from Guanajuato had been confronted in a residential area of Puerto Vallarta..

"There was a series of shots," Solis said. "One person was left (mortally) wounded at the place, others managed to flee — some on foot, others in vehicles."