Thousands of Venezuelans are expected to take to the streets on Saturday, following one of the longest power cuts in the country's recent history.
For decades Venezuela's electricity system has threatened to completely collapse – and although this power cut is not the first to hit the oil-rich country, it has been one of the most extended.
By Friday afternoon power was gradually being restored to large areas of the capital Caracas, as well as parts of Miranda state and Vargas, which is home to both the country's main international airport and seaport.
But the relief was short lived as the lights went off again, extending the power cut beyond 24 hours.
Phil Gunson of the Crisis Group NGO, and a long-time Caracas resident, tweeted that power supplies came on for a little over 90 minutes before cutting out again. "Much of the rest of the country has been living like this for year," he said.
Opposition leader Juan Guaido and President Nicolas Maduro are locked in a power struggle and asked their supporters once again to fill the streets of Caracas and other cities on Saturday.
"Tomorrow, I call on the Venezuelan people to make a huge statement in the streets against the usurper, corrupt and incapable regime that has plunged our country into darkness," Mr Guaido tweeted on Friday.
"We return to the streets and we won't leave until we reach the goal," said the National Assembly leader, who is recognised by more than 50 countries as Venezuela's interim president.
Mr Guaido is trying to force out Mr Maduro – whose re-election in May he described as illegitimate – to set up new elections.
Mr Maduro asked his backers to march against the same "imperialist power" he says is responsible for the power cut.
Meanwhile, Communications Minister Jorge Rodriguez said a hydroelectric power plant at Guri Dam in eastern Venezuela was hit by a cyber attack, most likely carried out by the US.
The power cut hit Caracas on Thursday just before nightfall. Its cause is still unknown.
As night fell, people could be heard banging saucepans could be heard around the capital, a form of protest often seen in South America.
Thousands of homes in Caracas – a crime-ridden city of two million people – were without water. Telephone services and access to the internet were knocked out and the subway system ground to a halt.
Witnesses described scenes of chaos at several hospitals as people tried to move sick relatives in the dark to clinics with emergency power, Agence France-Presse reported. Marielsi Aray, a patient at the University Hospital in Caracas, died when her respirator stopped working.
"The doctors tried to help her by pumping manually. They did everything they could, but with no electricity, what were they to do?" asked Jose Lugo, her distraught uncle.
The putrid odour of rotting flesh hung around the entrance to Caracas's main Bello Monte morgue on Friday where refrigerators stopped working and worried relatives gathered outside, waiting to be allowed to bury their dead.
An independent poll of 40 of Venezuela's biggest hospitals found that 79 patients died between November last year and January because of power cuts.
In the US, 16 Democratic politicians sent a joint letter to Secretary of State Mike Pompeo criticising what they described as "counterproductive" US strategy towards crisis-hit Venezuela.
"We write to express our deep concern regarding the Trump Administration's handling of relations with Venezuela, particularly its suggestions of military intervention, imposition of broad unilateral sanctions, and recent recognition of an opposition leader as interim president," the letter read.
Mr Pompeo said Mr Maduro was wrong to blame the US or any other country for Venezuela's woes.
"Power shortages and starvation are the result of the Maduro regime's incompetence," he tweeted.
Venezuela has suffered more than four years of recession that has seen poverty soar as citizens struggle with food and medicine shortages.