The Venezuelan opposition is increasingly under siege. Since Feb. 12, four of its leaders have been pointed out by the government of President Nicolás Maduro as part of a conspiracy in an attempted coup.

One of them, Antonio Ledezma, the mayor of Caracas, was arrested last week when dozens of members of the Bolivarian Intelligence Service, armed with long guns, broke into his office and took him away without showing a warrant for his arrest, as stated by his lawyers.

Mr. Ledezma was one of the signers of the National Agreement for the Transition, an open letter published in a newspaper that, according to Maduro, was the signal that was to mark the beginning of a U.S.-backed coup against his government.

The document was also promoted by Leopoldo López, an opposition leader who has been in prison since February 2014 under charges of promoting street violence, and former lawmaker María Corina Machado, who was ousted from her Congressional post after delivering a speech at the Organization of American States denouncing political repression in Venezuela.

Diosdado Cabello, president of the National Assembly and one of the main leaders of the ruling United Socialist Party of Venezuela (PSUV),  also linked Julio Borges—a legislator and the national coordinator of Venezuela's leading opposition party, Justice First—to the supposed plot to bring down the Government.

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This week PSUV lawmakers asked the attorney general’s office to open an investigation against Borges.

This sort of clampdown isn’t new. Twenty percent of opposition lawmakers are under judicial investigation and, as stated by the Venezuelan Association of Mayors, 33 out of 77 opposition mayors elected in December 2013 are currently subject to judicial processes.

But the crackdown on dissenters goes well beyond the main opposition leaders. This week, a Bolivarian National Police officer was charged with intentional homicide in the death of a 14-year-old boy, Kluiverth Roa, who was shot with rubber bullets during a protest in the western city of San Cristóbal.

In the first 53 days of this year, 151 people have been arrested for taking part in demonstrations against the government, according to the local nongovernment organization, Foro Penal Venezolano.

“We are witnessing the collapse of the regime,” Machado told Fox News Latino. “The regime has chosen to move forward in an attempt to silence all dissenters: union leaders, students, journalists and politicians. They know that 80 percent of Venezuelans are asking for a profound change and that we have understood that the change won't be possible as long as Maduro and his regime hold onto power.”

Machado added, “Due to the pressure of the citizens, they have decided to go more radical.”

She pointed to the National Agreement for the Transition as the main trigger of the crackdown.

“The regime has realised that we have … a vision for the country, a political, economic and social program to solve our problems while taking special care of our most vulnerable citizens,” she said.

Carmen Beatriz Fernández, the managing director of the consulting group DataStrategia and the author of books about electoral politics, believes that the parliamentary elections to be held at the end of the year are part of the reason for the repression.

“The government doesn't want people to get to the polls,” Fernández told FNL. “They want to step up the pressure because they are terrified to get a pitiful result. Latest polls show a gap of 35 points in favor of the opposition.”

She went on to say, “What we will probably see next is a move to take Ledezma, Borges and Machado out of the electoral battlefield. They want to pick up their adversaries.”

Historian Margarita López Maya agreed that administration is trying to weaken the opposition.

"The arrest of Ledezma was a very showy scene,” López Maya told FNL. “It was meant to encourage not only fear but, above all, despair among opposition supporters.”

She noted that since Maduro came to power, he consistently attempted to stigmatize and criminalize the opposition.

“According to the narrative of Chavismo, all opposition forces are willing to engage in a military coup, and any dissent is treated as an effort to destabilize the regime,” she told FNL. “The government controls all the public sector media and most of the private ones. If they repeat 100 times a day these attacks on the opposition, they might get a result.”

The Democratic Unity Platform (MUD), a coalition of 27 opposition parties, began trying to mobilize Venezuelans to protest the arrest of Ledezma, but they also set a date for internal elections to select candidates to the National Assembly.

"The government wants to rid itself of the commitment to elections by outlawing the opposition," said Jesús Torrealba, MUD’s executive secretary. "If the cost of doing politics is persecution and death, the only thing left is violence. But it is not our path."

The former congresswoman, María Corina Machado agreed, saying, “In Venezuela, those who support military coups are the ones that hold the power nowadays. We will firmly stand by our commitment to democracy. We will keep fighting.”

The Associated Press contributed to this report.