Dressed in white and chanting "this government will fall", thousands of opposition supporters flooded Venezuela's capital on Thursday to press for a recall referendum this year against Socialist President Nicolas Maduro.

With protesters from the Amazon jungle to the western Andes, the opposition coalition aimed to collect at least one million people at rallies across the capital to show anger at Maduro and Venezuela's deep economic crisis.

A rival pro-government rally was also planned in the centre of the city.

"We are going to defeat hunger, crime, inflation and corruption. They've done nothing in 17 years. Their time is finished," said Naty Gutierrez, 53, surrounded by thousands of people clad in white and waving national flags at one gathering point.

The rallies come at a volatile time for Venezuela, stricken by shortages of food and medicine, outbreaks of violent crime and looting in the once-rich major oil exporter.

Hundreds of soldiers and police in armored cars were deployed.

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Opposition leaders were hoping to bring hundreds of thousands of people  on to the streets to demand quick action on a recall vote that Maduro has vehemently resisted.

"All of Venezuela is mobilising for the right to vote," said Jesus Torrealba, the head of the main opposition coalition, the Democratic Unity Roundtable (MUD).

He called it "the most important political mobilisation of our recent history" and vowed that marchers would defy the government's "strategy of fear, blackmail and intimidation".

Triple-digit inflation, a third year of recession, shortages of basic goods, and long lines at shops have exasperated many of Venezuela's 30 million people. The frustration was expressed in a resounding opposition election win in a December legislative vote.

"People are saying that the current economic situation has been deteriorating to a point that they cannot live any longer," said Al Jazeera's Teresa Bo, reporting from Buenos Aires.

"The only solution to this situation is a recall referendum and possibly a new leadership." 

Maduro on alert

Maduro, 53, says the opposition-dubbed "Takeover of Caracas" on Thursday is a front for violence, akin to a short-lived 2002 coup against his mentor Chavez, who died of cancer three years ago. Maduro has failed to replicate his charismatic predecessor's popular appeal, and his ratings in opinion polls have fallen to just over 20 percent.

"I'm ready for everything ... we will not allow a coup," Maduro told supporters late on Wednesday. He said various people were detained that had been planning to place explosives and kill fellow opposition supporters to discredit the government and sow chaos. 

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He did not give details, but rights groups and opposition parties said that authorities had arrested well-known activists in the run-up to the protests. They said that more than a dozen opposition campaigners and supporters were in custody.

The pro-government "Chavistas" - named after Maduro's predecessor, the late Hugo Chavez - staged rallies on Tuesday and Wednesday.

They called on their supporters to "defend the revolution" with a massive turnout on Thursday at what they call "The Taking of Venezuela."

"Don't provoke us because not only are we going to block up Caracas so that no one can enter, but we will also make sure that no one can leave," said former National Assembly speaker Diosdado Cabello.

Maduro has accused the opposition of planning a "coup" and threatened to imprison opposition leaders if violence breaks out at Thursday's protests.

"Squeal, cry or scream, jail is where they'll go," he said.

The president said on Wednesday that he would ask the Supreme Court to consider a request to lift immunity from prosecution granted to public officials, starting with the country's politicians.

The move would allow him to target opposition legislators who control the National Assembly.

'Recall hunger' 

The referendum's timing lies at the heart of the battle.

If it takes place before January 10 and Maduro loses, new elections must be held. If he loses in a recall after that date, he would simply turn over power to his hand-picked vice president.

The polling firm Venebarometro recently estimated that 64 percent of the electorate would vote against Maduro.

Maduro blames the crisis on the collapse of oil prices and an "economic war" by businesses.

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But he faces deep public discontent over shortages of basic goods and an inflation rate projected to hit 720 percent this year.

In 2014, the government crushed weeks-long, anti-government protests in a confrontation that left 43 dead and prominent opposition leaders in prison.

Former presidential candidate Henrique Capriles, who distanced himself from the protests in 2014, told AFP that this time the opposition is banking on mass mobilizations and international pressure to get the government to accept the recall election

Source: Al Jazeera News and agencies