This June 13, 2006 file photo shows then Tijuana Mayor Jorge Hank Rhon in his City Hall office, in Tijuana, Mexico. A Mexican official says that Hank Rhon has been arrested on suspicion of illegal weapons possession. (DAVID MAUNG/AP)

Federal prosecutors in Mexico on Wednesday formally charged the former mayor of Tijuana, one of the country’s wealthiest men, with illegal possession of a large cache of weapons and ammunition.

The decision to prosecute Jorge Hank Rhon, a gambling tycoon and a major figure in the opposition party in Mexico, has sparked a political squall here, as members of his Institutional Revolutionary Party (PRI) denounce the arrest as election-season mischief orchestrated by the ruling party of President Felipe Calderon.

Rumors about Hank’s alleged ties to Tijuana drug traffickers and money launderers have dogged the 55-year-old racetrack owner for years, but his arrest by soldiers Saturday night at his luxe Tijuana estate, which includes a private zoo, soccer stadium and casino, led to the first public charges against him.

Hank was transferred to the El Hongo State Penitentiary east of Tijuana, along with 10 members of his security team, according to the Mexican attorney general.

When soldiers raided Hank’s compound on Saturday, they confiscated 88 weapons, including 49 high-caliber rifles and various pistols, along with 8,944 rounds of ammunition, that are restricted for military use in Mexico, according to prosecutors and the Mexican army.

Hank’s family members and lawyers say the weapons belong to his security detail, which protects his family and his extensive holdings, and that he has nothing to do with the arsenal.

Mexico has some on the most strict gun-control laws in the world, on paper, even as the country is awash in illegal weapons, many used by criminal gangs, but many held by ordinary citizens. The country of 110 million has just one gun store, and it is run by the military.

“We as a party, we will not allow a witch hunt during an election season and we will watch very closely what evidence is produced in the case against Hank Rhon,” said PRI spokesman David Penchyna.

Asked by a reporter if she thought her husband was a victim, Hank’s wife, Maria Elvia Amaya, said, “Yes, I believe so, because it has always been this way, all the gossip, the dark rumors, but they have never been able to go after him. Everything he does, the government knows about, the intelligence services know about.”

Calderon officials denied there was a political motive.

“There is no witch hunt, of course not. Every case is supported by evidence,” Mexico’s new attorney general, Marisela Morales, said at a news conference.

Elected mayor of Tijuana in 2004, during a height of the drug violence there, Hank resigned in 2007 to run for governor. He lost to Baja California’s current governor, a member of Calderon’s ruling party. Hank says he might run for governor again in 2013.

Earlier this week, several thousand of his supporters staged a rally in Tijuana and shouted slogans demanding his release.

Hank heads Grupo Caliente, which owns 200 off-track parimutuel betting and bookmaking outlets throughout Mexico, Austria, Brazil, Equador, Panama, Paraguay, Peru, Uruguay, Venezuela and the Caribbean.

For years, the award-winning weekly investigative magazine in Tijuana, Zeta (no relation to the drug cartel of same name), has run a full-page advertisement asking Hank why one of his employees killed star journalist Hector Felix Miranda, known as Felix the Cat, who was assassinated in 1988.

The political commentator Denise Maerker noted this week that the top officials of PRI have not risen to Hank’s defense and have sent their surrogates out to make statements. “They haven’t said anything that will compromise them,” Maeker wrote. “This is a wise strategy.”