Guzman Salazar was said to be one of four people to have been identified among six abducted.
A son of drug lord Joaquin "El Chapo" Guzman was among a group kidnapped from a bar in the Mexican resort city of Puerto Vallarta, authorities confirmed Tuesday.
Seven gunmen in pickup trucks swooped on the upscale bar and restaurant Monday around dawn and abducted several victims.
Investigators said it was likely part of a settling of scores between rival drug cartels.
"Jesus Alfredo Guzman Salazar, 29, is the son of Joaquin (Guzman) Loera, this has been confirmed," and he is among those being held, regional public prosecutor Eduardo Almaguer told a news conference.
He said Guzman Salazar was one of the four people who have so far been identified among six abducted.
He added that "various security agencies" had confirmed that Guzman Salazar was the son of "El Chapo."
The elder Guzman is the jailed boss of the powerful Sinaloa cartel and one of the most notorious drug lords in the world.
Authorities initially said 10 to 12 people had been kidnapped, but after analyzing security camera footage and interviewing witnesses, they said there were in fact six men abducted.
They had earlier said that one of them may have been another of Guzman's sons, Ivan "El Chapito" (Little Chapo) Guzman.
"El Chapo" staged a spectacular jailbreak last year only to be recaptured in January.
He is now in a maximum security federal prison in the northern city of Ciudad Juarez and fighting extradition to the United States.
The chief prosecutor said only fake identity documents had been found at the scene of Monday's kidnapping, in a posh restaurant called La Leche in the Pacific coast city's chic hotel district.
Prosecutors said initial evidence suggested a rival cartel called Jalisco New Generation was behind the abduction.
Jalisco New Generation emerged in Puerto Vallarta in 2010 after the death of the local boss of the Sinaloa cartel, Ignacio "Nacho" Coronel.
It has become one of violence-plagued Mexico's most powerful drug gangs in recent months by defying the authorities with a series of brazen attacks and ambushes.