BOGOTA, Colombia — Electoral authorities claimed that Nicolás Maduro, Venezuela’s deeply unpopular president, had won a third term in Sunday’s election, sparking accusations that his authoritarian regime had committed massive fraud to steal victory from opposition candidate Edmundo González.

After hours of delays and uncertainty, Elvis Amoroso, president of the National Electoral Council and a close Maduro ally, appeared before journalists shortly after midnight on Monday. He declared that Maduro had won with 51% compared to 44% for González, with 80% of the votes counted.

However, opposition leader María Corina Machado insisted that González, a 74-year-old retired diplomat who took Machado’s place on the presidential ballot when the regime banned her from running, had won 70% of the vote compared to 30% for Maduro.

“Venezuela has a new president, and he is Edmundo González,” Machado told a crowded news conference in Caracas.

As evidence, Machado cited several exit polls and quick counts showing González heading toward a landslide victory, as well as paper receipts from voting machines. An exit poll published by the U.S. firm Edison Research showed González leading Maduro 65% to 31% while nearly all pre-election polls predicted that he would trounce Maduro.

“We won in every demographic, in every state,” Machado said. “It was overwhelming. We won and the whole world knows this. Even the regime knows what happened.”

The National Electoral Council waited for six hours after the polls closed to announce Maduro’s victory, indicating that his inner circle may have been debating how to handle the results. After his regime failed to derail the opposition campaign through dirty tricks and by banning Machado, many political analysts believed that Maduro would resort to stealing the election.

“100% predictable,” Eric Farnsworth, vice president of the Council of the Americas think tank, said of Maduro’s claim to victory.

Maduro, 61, was first elected in 2013 following the death of his mentor, Hugo Chávez, who founded Venezuela’s socialist revolution in 1999. But Maduro is widely despised for leading Venezuela into its worst economic crisis in history which prompted nearly 8 million Venezuelans, about a quarter of the population, to flee the country. He has also been indicted by the U.S. for drug trafficking and terrorism while his regime is being investigated by the International Criminal Court for crimes against humanity.

“I have a clean conscience,” Maduro told supporters gathered at the Miraflores presidential palace. “In this new term that you have given me, I pledge that I will put my life on the line to transform Venezuela and lead us toward a prosperous future of economic growth, peace and social happiness.”

The Biden administration, which has threatened to reimpose sanctions on Venezuela’s vital oil industry, and other foreign governments immediately cried foul.

“We have serious concerns that the result announced does not reflect the will or the votes of the Venezuelan people,” Secretary of State Antony Blinken said. “It’s critical that every vote is counted fairly and transparently, that election officials immediately share information with the opposition and electoral observers without delay and that the electoral authorities publish detailed tabulation of votes.”

Chilean President Gabriel Boric wrote on X: “The Maduro regime must understand that the results they have published are difficult to believe. Chile will not recognize any results that cannot be verified.”

Brazil, Colombia and other Latin American nations expressed similar concerns.

Anger and frustration with Maduro was evident on Sunday, with several regime loyalists loudly booed when they showed up at polling places to vote. Confident that González would win, some Venezuelans chanted what has become a popular opposition slogan: “It’s going to fall. It’s going to fall. This regime is going to fall!”

Some Venezuelans were so eager to cast their ballots for the opposition that they lined up at polling places the night before the election. Elidio Santana, who sells bottled water on the streets of Caracas, stood in line for four hours to vote for González.

“We’ve been waiting for 25 years” for a change of government, Santana said, adding that a few more hours wouldn’t matter. “We are fed up. This country needs a change.”

Of the estimated 5.5 million voting-age Venezuelans living abroad, only about 69,000 were able to register to vote due to red tape put in place by the Maduro regime. One migrant who did manage to vote was Carolina Martínez, a 50-year-old nurse who lives in neighboring Colombia but returned to Venezuela to cast her ballot. She predicted that a González victory would convince Venezuelans living abroad to repatriate.

“A lot of people want to come back to Venezuela and to see their homeland prosper again,” said Martínez, whose four sons also live abroad.

But with both sides claiming victory, Venezuela could face an extended period of unrest as many opposition supporters pledged to protest in the streets. González urged them to be peaceful as the opposition goes about gathering evidence, such as the paper receipts from voting machines, that he won the election.

“Our fight will continue,” González told a news conference early Monday. “We won’t stop until the will of the people is respected.

Carrie Kahn contributed from Caracas.