Venezuela prepared Friday for a possible showdown between opposition protesters and government forces ahead of a vote that critics decry as a final step toward authoritarian rule in the South American nation.

Residents here in the sprawling capital poured into supermarkets, already struggling with food shortages, to stockpile what they could amid fears of violence. Flash points emerged in parts of the city, with clusters of protesters clashing with security forces who fired tear gas. Many streets were calm, though, some even eerily quiet. 

“I’m going to stay home all weekend, because I feel there will be violence,” said Rosa Aponte, 45, who was shopping in a packed grocery store in wealthier eastern Caracas, buying bread, plantains, juice, yogurt and sardines. “I do not want to take the risk.” 

Ahead of Sunday’s vote, the socialist government of President Nicolás Maduro — the anointed successor of leftist firebrand Hugo Chávez, who died in 2013 — issued a ban on public gatherings and protests through Tuesday. The opposition answered with a vow to pour into the streets nationwide, although exactly how many would heed that call remained unclear.

Demonstrators at a rally in Caracas against Venezuelan President Nicolás Maduro's government on July 27, 2017. (Ueslei Marcelino/Reuters)

In Caracas, a downpour dampened the early turnout, although clusters of demonstrators had begun to set up roadblocks. Rising tensions led the U.S. State Department late Wednesday to order family members of American staff at its embassy in Caracas to leave the country and authorize voluntary departures of personnel. Images on social media showed massive lines at Caracas’s Maiquetia International Airport.

Opponents are boycotting Sunday’s vote, which would create a super-congress that could prolong Maduro’s rule. A whopping 6,120 candidates are running in the election, including Maduro’s son and wife, former officials and rank-and-file government supporters. The new institution would possess great powers, including the right to change the constitution and supplant the National Assembly. 

Although robbed of its power by the government-controlled supreme court, the assembly is dominated by the opposition, which won it in a landslide in 2015. 

Roads were blocked Friday in eastern Caracas, but the city center appeared relatively normal, as did western parts of the capital.

Demonstrators said fear was apparently keeping some people away. 

“I feel a bit sad [there aren’t more people here], but I am here for Venezuela,” said a 29-year-old protester who declined to give her name. She was stuffing fuses inside molotov cocktails at a spot in eastern Caracas where a small group of demonstrators was battling police.

“Nothing is going to stop us. We need to stop this country from becoming a second Cuba,” she said. 

(Multimedios VTV)

One remote hope to prevent the vote had rested on secret, indirect talks mediated by former Spanish prime minister José Luis Rodríguez Zapatero. In an interview, Julio Borges, president of the National Assembly, acknowledged that Zapatero had delivered messages between the opposition and government.

But he described that process as now being effectively dead and said there was “zero” hope of a deal that would forestall the vote.

“There are absolutely no negotiations happening now,” Borges said. “No agreements have been reached. I see zero chance that the government will back down before Sunday. Zero.”

The crisis is mounting amid shortages of food and medicine and a 16 percent drop in the already-rock-bottom black-market value of the bolívar, the local currency, in just the past week. The United States this week sanctioned 13 more Venezuelan officials. The Trump administration is weighing far tougher steps, including a deeply painful embargo on Venezuelan oil, if Maduro does not call off the vote. 

Other nations in Europe and beyond have pledged to follow suit. Mexican officials said this week that they would impose sanctions on Venezuelan officials. “Mexico once again expresses its preoccupation with the grave crisis that Venezuela is going through,” the Mexican Foreign Ministry said in a statement, calling on Maduro “to fully restore democracy and the rule of law in a peaceful way.” 

Maduro argues that the new assembly will bring peace and stability as well as empower citizens in poor neighborhoods. His critics call the effort a ploy to replace the National Assembly and consolidate power after four months of protests that have left at least 112 people dead.

Rachelle Krygier in Caracas and Josh Partlow in Mexico City contributed to this report.