The outage began shortly after 1 p.m. (1700 GMT) and appeared to have affected as many as 16 of Venezuela's 23 states, according to reports on social media. Officials declared that power had been fully restored by early evening, but hours later the lights went out again in much of the country.
As with the previous outage, the government of President Nicolas Maduro sought to blame U.S.-backed opponents, accusing them of sabotaging the Guri dam, source of the bulk of Venezuela's electricity.
"A macabre, perverse plan constructed in Washington and executed with factions of the extreme Venezuelan right," Vice President Delcy Rodriguez declared on state television, describing it as an "electromagnetic" assault.
Officials said the "attack" had been controlled, but their assurances, similar to ones the last time around, did little to calm the anger of residents in Caracas who filled traffic-clogged streets as they walked home after subway service in the capital was suspended. Their patience grew increasingly thin when a second outage struck late into the night, leaving neighborhoods pitch black.
On social media, Venezuelans reported outages in Caracas and much of western Venezuela. Some said residents were banging pots and pans in the darkness in a sign of the nation's mounting tensions. The latest outages come as President Nicolas Maduro tries to keep his grip on power amid a revived opposition movement and punishing economic sanctions from the United States.
Twenty-seven-year-old restaurant manager Lilian Hernandez said she was bracing for the worst.
"We Venezuelans suffer all kinds of problems," said Hernandez, who had just recently managed to restock food that spoiled during the previous outage.
Netblocks, a non-government group based in Europe that monitors internet censorship, said the early afternoon outage had knocked offline around 57 percent of Venezuela's telecommunications infrastructure. The second failure left nearly 90 percent of the country offline, the organization said.
The Trump administration, which has made no secret of its desire to remove Maduro, has denied any role in the outages. Electricity experts and opposition leader Juan Guaido fault years of government graft and incompetence.
"This outage is evidence that the dictator is incapable of resolving the crisis," Guaido wrote on Twitter Monday.
Meanwhile, as Venezuela's economic and political crisis deepens, many seem resigned to continuous disruptions in their daily routines.
"The important thing is for people not to get desperate," said William Rodriguez, who sells books at a kiosk under a downtown highway overpass.
Also Monday, the rift between Russia and the United States over how to resolve the crisis in Venezuela widened following the arrival of Russian military personnel to support Maduro.
In a telephone call, U.S. Secretary of State Mike Pompeo told Russian Foreign Minister Sergei Lavrov that "the United States and regional countries will not stand idly by as Russia exacerbates tensions in Venezuela," the State Department said. Pompeo said "the continued insertion of Russian military personnel" in Venezuela could prolong the country's problems and urged Russia "to cease its unconstructive behavior."
Lavrov countered during the call that "Washington's attempts to organize a coup in Venezuela and the threats directed against its legitimate government represent a violation of the U.N Charter and blunt interference into internal affairs of a sovereign nation," according to the Russian foreign ministry.
Pompeo's call to Lavrov came after a Venezuelan official said Russian aircraft arrived in Caracas this past weekend as part of ongoing military cooperation. Reports that two Russian air force planes arrived could not be independently confirmed.
The U.S. and dozens of other countries support Guaido, who says Maduro's re-election last year was rigged. Maduro alleges the U.S. and Guaido are plotting a coup.
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