A man presented by authorities as Alfredo Guzman Salazar is shown to the media in Mexico City, Thursday, June 21, 2012. The man arrested Thursday as the presumed son of Joaquin “El Chapo” Guzman is really Felix Beltran Leon, 23, and not Alfredo Guzman Salazar, as the Mexican Navy had presented him, the Attorney General’s Office said Friday. (Eduardo Verdugo/AP)

In a case that now appears more embarrassment than triumph for the Mexican government and its partners in U.S. law enforcement, the man whom Mexican marines captured and paraded before cameras Thursday and described as a smuggling kingpin and son of Sinaloa drug lord Joaquin “El Chapo” Guzman may not be his son at all.

The young man arrested in a dawn raid by Mexican marines is Felix Beltran and not Chapo’s son, his attorney, Veronica Guerrero, said during a news conference. She said her client is an innocent car dealer. The man’s wife and a lawyer told the Associated Press the Mexican marines planted weapons.

“If this is true, and it’s a mistake, it is a terrible one,” said Sergio Aguayo, a professor and political analyst. “It confirms our worst suspicions” of incompetence and an over-reliance on U.S. intelligence and hand-holding.

On Thursday, Mexican navy officials said they had arrested Jesus Alfredo Guzman, the “presumed” son of Chapo, the most wanted drug trafficker in Mexico, in a suburb of Guadalajara. At a news conference, with their captive on display, the officials said the young man was Chapo’s son and a major cartel operative. He was posed standing in front of a dozen weapons, including four grenades, and $160,000 in cash, mostly U.S. dollar bank notes.

The U.S. Drug Enforcement Administration, whose intelligence was credited by the Mexicans with helping locate the suspect, responded by applauding the arrest of Chapo’s son, known as Afredillo, or Little Alfred, who has been indicted in the United States as a top-level operative of the Sinaloa cartel. The Washington Post reported on the arrest.

On Friday, however, the newspaper Riodoce in the Sinaloa capital of Culiacan, home of the Sinaloa cartel, said the young man was definitely not Chapo’s son.

The Mexican marines said they were seeking more information and did not comment on the identity of the man. In a brief statement, the Mexican attorney general’s office said it was trying to learn his true identity but also mentioned that the initial information about his location and identification was given by U.S. agencies.

U.S. law enforcement officials, speaking on the condition of anonymity, said there was confusion about who was in the house the Mexicans raided and that it appears it was not Chapo’s son.

Mexicans are suspicious that, in the closing days of the presidential election, the ruling party will arrest drug cartel leaders to boost the campaign of Josefina Vazquez Mota. If it turns out that the man arrested is not Chapo’s son, it will probably hurt Vazquez at the polls.