CARACAS, Venezuela (AP) -- Two of Venezuela's leading opposition figures were taken from their homes in the middle of the night by state security agents on Tuesday, in President Nicolas Maduro's first moves against his enemies since a widely denounced vote giving his government nearly unlimited powers.

The wife of opposition leader Leopoldo Lopez posted what appeared to be video of him being taken from their home after midnight.

"They've just taken Leopoldo from the house," Lilian Tintori wrote on Twitter. "We don't know where he is or where they're taking him."

12:27 de la madrugada: Momento en el que la dictadura secuestra a Leopoldo en mi casa. No lo van a doblegar! pic.twitter.com/0EdlQvEGXS — Lilian Tintori (@liliantintori) August 1, 2017

Allies of former Caracas Mayor Antonio Ledezma posted video online of a man who appeared to be the opposition leader being taken by state security as a woman screams for help for neighbors.

"They're taking Ledezma!" she cries. "It's a dictatorship!"

Lopez was detained three years ago after protests against Maduro's government and sentenced to more than a decade in prison on charges that include inciting protesters to violence. He was released last month to serve the rest of his term under house arrest. Ledezma, a former Caracas mayor, was also detained in 2015 and has been under house arrest.

Both have recently posted videos online denouncing Maduro's decision to hold a vote for a constitutional assembly with the power to overhaul Venezuela's political system.

Maduro said Monday evening he had no intention of deviating from his plans to rewrite the constitution and go after a string of enemies, from independent Venezuelan news channels to gunmen he claimed were sent by neighboring Colombia to disrupt the vote as part of an international conspiracy led by the man he calls "Emperor Donald Trump."

"They don't intimidate me. The threats and sanctions of the empire don't intimidate me for a moment," Maduro said on national television. "I don't listen to orders from the empire, not now or ever ... Bring on more sanctions, Donald Trump."

A few hours earlier, Washington added Maduro to a steadily growing list of high-ranking Venezuelan officials targeted by financial sanctions, escalating a tactic that has so far failed to alter his socialist government's behavior. For now, the Trump administration has not delivered on threats to sanction Venezuela's oil industry, which could undermine Maduro's government but raise U.S. gas prices and deepen the humanitarian crisis here.

The sanctions came after electoral authorities said more than 8 million people voted Sunday to create the constitutional assembly -- a turnout doubted by independent analysts while the election was labeled illegitimate by leaders across the Americans and Europe.

Venezuela's National Electoral Council said turnout in Sunday's vote was 41.53 percent, or 8,089,320 people. The result would mean the ruling party won more support than it had in any national election since 2013, despite a cratering economy, spiraling inflation, shortages of medicine and malnutrition. Opinion polls had said some 85 percent of Venezuelans disapproved of the constitutional assembly and similar numbers disapproved of Maduro's overall performance.

Opposition leaders estimated the real turnout at less than half the government's claim in a vote watched by government-allied observers but no internationally recognized poll monitors.

An exit poll based on surveys from 110 voting centers by New York investment bank Torino Capital and a Venezuela public opinion company estimated 3.6 million people voted, or about 18.5 percent of registered voters.

The national electoral council's vote counts in the past had been seen as reliable and generally accurate, but the widely mocked announcement appeared certain to escalate the polarization and political conflict paralyzing the country.

The constituent assembly will have the task of rewriting the country's constitution and will have powers above and beyond other state institutions, including the opposition-controlled congress.

Maduro has said the new assembly will begin to govern within a week. Among other measures, he said he would use the assembly's powers to bar opposition candidates from running in gubernatorial elections in December unless they sit with his party to negotiate an end to hostilities that have generated four months of protests that have killed at least 120 and wounded nearly 2,000.

Along with the U.S., the European Union and nations including Argentina, Canada, Colombia, Mexico, Panama, Paraguay, Spain and Britain criticized Sunday's vote. Maduro said he had received congratulations from the governments of Cuba, Bolivia and Nicaragua, among others.

Maduro called the constitutional assembly in May after a month of protests against his government, which has overseen Venezuela's descent into a devastating crisis during its four years in power. Due to plunging oil prices and widespread corruption and mismanagement, Venezuela's inflation and homicide rates are among the world's highest, and widespread shortages of food and medicine have citizens dying of preventable illnesses and rooting through trash to feed themselves.