Mr Maduro claimed only 30,000 demonstrators turned out. Organisers of the so-called "Taking of Caracas" said there were many more and called for a new show of strength in six days. Reuters said there were hundreds of thousands of demonstrators.
“Today we've defeated a coup attempt that sought to fill Venezuela and Caracas with violence and death,” Mr Maduro said, without providing details about the accusations. “We're still looking for several criminals that paid to massacre the people.”
The Associated Press said the anti-government rally filled dozens of city streets as protesters demanded electoral authorities allow a recall referendum against Mr Maduro to move forward this year. The government used tear-gas to disperse some protesters, and jailed opposition leaders and blocked foreign media ahead of the demonstration.
Jesus Torrealba, secretary-general of the Democratic Unity alliance, said that on September 7, protesters will march to the offices of the pro-government electoral council in cities across the country.
“Today is the beginning of the final stage of our fight,” he said.
The protests took place against a backdrop of mounting economic crisis. Shows in the country’s major cities are often lacking in basic items and ordinary people are frequently forced to endure long queues. Reports suggest large numbers of people have already left the country for neighboring Colombia.
Ahead of the the protests, Mr Maduro’s government has jailed several prominent activists and deploying security forces across the city.
Last week, Daniel Ceballos of the opposition Popular Will party was returned to prison after having spent a year under house arrest awaiting trial on charges of rebellion. The Interior Ministry said he was planning on escaping from house arrest to carry out acts of violence during Thursday’s rally.
Meanwhile, a number of foreign journalists have been blocked from attending the protests. NPR's John Otis said he was turned around at Caracas airport, along with Marie-Eve Detoeuf of Le Monde, and Cesar Moreno, a reporter for Colombia's Radio Caracol. He said a few days ago an Al-Jazeera TV crew was also turned back at the airport.
Mr Maduro has accused his opponents of plotting violence during the march to pave the way for a coup such as the one that briefly toppled Mr Chavez in 2002. A number of the current opposition leaders backed that coup.
“If they're coming with coups, ambushes and political violence, the revolutionary will provide an uncommon and overwhelming response,” Mr Maduro said on Tuesday.
Shortly after dawn Thursday, a few hundred people dressed in the yellow, red and blue colors of Venezuela’s flag began walking toward the three large avenues in eastern Caracas where demonstrators were to concentrate after midday.
Some held signs saying “I revoke”, a terse way of expressing support for the move to end Maduro's mandate as president, the AP said.
Among those taking part in the march, which organiaers had hoped would draw 1 million people, were some 100 members of the Piaroa and Jiwi indigenous tribes. They arrived in Caracas on Wednesday for the protest after travelling more than 375 miles - by foot, canoe and bus - from the Amazon rainforest.
“We came to see if they’ll free the political prisoners,” said Miguelina Caballero. She was referring to someone from her Piaroa tribe who had been jailed for alleged fraud during December’s congressional elections, a case the government used to disqualify three indigenous leaders from taking seats in the opposition-controlled legislature.
The opposition has staged a half-dozen or so marches this year, some of which ended in clouds of tear gas as hard-core activists clashed with riot police, but posed no major risk to Mr Maduro’s grip on power.
Even the anti-government protests in 2014 that were blamed for more than 40 deaths failed to rally the huge numbers now sought for Thursday’s march by the Democratic Unity alliance.
The opposition hopes to force electoral authorities to allow a recall vote this year. If Mr Maduro loses, new elections would be held and polls indicate the opposition would win.
But if a vote is delayed until after January 10, and Mr Maduro loses, his vice president would finish his term ending in 2019.
Reuters said that extra police and troops were positioned around Caracas, and there were roadblocks on most major routes, with buses being blocked and traffic crawling. Security forces fired teargas on one highway where buses were stopped but people tried to continue on foot, pro-opposition broadcaster VivoPlay said.
“All they are interested in is staying in power,” said construction worker Luis Palacios, 59, from the poor Caracas neighborhood of Petare. “We want change, we are hungry.”
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