Mexican officials have confirmed that Jesus Alfredo Guzman, 29, who is El Chapo's son from his first marriage, was one of the men kidnapped from the resort.
Previously, it was believed that El Chapo's son Ivan Guzman was among those taken in Puerto Vallarta. But Jalisco Attorney General Eduardo Almaguer told a news conference that Alfredo was the son who was abducted.
'At this moment, we have identified four of the kidnapped,' Almaguer said, 'one of them being Jesus Alfredo Guzman'.
He said the identification was made through items found in the vehicles and forensic work at the scene.
Almaguer says the kidnappers appear to belong to the state's dominant Jalisco New Generation drug cartel and the victims are from the rival Sinaloa cartel.
Seven gunmen in pickup trucks descended on the upscale bar and restaurant around dawn and abducted the group, in what investigators have called a likely settling of scores between rival drug cartels.