The mayor of Venezuela's second largest city is missing, apparently the latest casualty of a crackdown on opposition by President Hugo Chavez that observers are calling outright persecution.

Manuel Rosales ran against Chavez for president in 2006 and lost, but last year he was elected mayor of the port city of Maracaibo, home to over 3 million people.

After Chavez vowed on national TV to throw Rosales in jail, the government filed corruption charges against the 56-year-old mayor. Two weeks ago, Rosales dropped out of sight. Supporters say he is hiding — from an enemy who now has the power to crush all opposition.

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Rosales isn't alone in fearing retribution. Antonio Ledezma, another Chavez opponent, was elected mayor of Caracas in 2008 but is being barred from his office by his own police force, which attacked him when he tried to enter.

"It is hard to understand — a mayor can't get into his own office," Ledezma said. "The people there have guns. They have a license for guns, a license for crime."

Political analysts once used the word "authoritarian" to describe Hugo Chavez. Now they have begun to use the word "dictator" after what's happened to Ledezma and others.

"What's going on is persecution," said Susan Purcell, director of the Center for Hemispheric Policy at the University of Miami. "[Y]ou have a political system where people don't have rights, the government controls all the means of communication ... and (Chavez) just doesn't want anybody to come up and challenge him. This is the usual behavior of dictators."

The crackdown began after Chavez won the battle to remove presidential term limits, amending the nation's constitution in a February referendum. The political opposition has learned to fear imprisonment, but some fear violence as well.

"I have already been victim of three murder attempts," said Leopoldo Lopez, mayor of Chacao, now a part of the capital of Caracas. "And two years ago was the last murder attempt and a fellow worker, Carlos Mendoza, was killed — he died in my arms."

While the mayor of Maracaibo hides, his wife, a mother of 10 children, is speaking out.

"It is something like out of a movie. I have to go to secret places to talk to my husband," Eveling Trejo de Rosales told FOX News. "Tanks drive by our house. What do I tell my 3-year-old child, who cries at night and wants to know where his father is?"

It is not clear where Rosales is. The Chavez government says he has gone to Panama or the United States. Supporters say he remains inside Maracaibo, where technically he is still mayor, although even his supporters have difficulty explaining how a mayor in hiding can run a major city.

"The mayor was just here recently. Honestly. He signed some decrees," an aide told FOX News. "Right now I'm the acting mayor, but he is the real mayor. I am simply implementing his decisions."

Chavez is not popular in all parts of the country. FOX News witnessed residents of Maracaibo setting his effigy on fire — but the governors and mayors who oppose the Venezuelan president are fast losing their powers, and sometimes their liberty.

The president's former defense minister, Gen. Raul Baduel, was arrested at gunpoint by government intelligence agents last week, charged with corruption and thrown in jail awaiting trial.

The next opponent could be what's left of the media. Chavez urged this week that sanctions be imposed on the one television station that still criticizes the president.

Steve Harrigan currently serves as a Miami-based correspondent for Fox News Channel (FNC). He joined the network in 2001 as a Moscow-based correspondent.