President Nicolas Maduro's government won a majority of governorships in Venezuela's regional election on Sunday, drawing fraud suspicions from the opposition whom polls had shown poised for a big win.

Electoral board president Tibisay Lucena said the ruling Socialist Party took 17 governorships, versus five for the opposition Democratic Unity coalition, with results irreversible in all but one of the OPEC member's 23 states.

"'Chavismo' is alive, in the street, and triumphant," a beaming Maduro, 54, said in a speech to the nation, referring to the ruling movement's name for former president Hugo Chavez.

Minutes earlier, opposition leaders had warned the pro-government election board was about to announce results that contradicted their certainty of a "gigantic" victory.

"We have serious suspicions and doubts," election campaign chief Gerardo Blyde told reporters.

Though opposition leaders drew short of presenting detailed accusations or evidence of fraud, rank-and-file supporters expressed disgust and disillusionment at what they said was obvious vote tampering.

The election board used a different company for Sunday's vote machines after its former partner, London-based Smartmatic, accused it of manipulating a July election for a new legislative superbody by at least 1 million votes.

One survey prior to Sunday's vote had given the opposition 44.7 percent of voter intentions versus 21.1 percent for the government - close to Maduro's own approval rating of 23 percent.

The opposition's handful of five governorship victories included the restive Andean states of Merida and Tachira, plus the oil-producing region of Zulia.

The government won back populous Miranda state, which includes part of Caracas, for an up-and-coming star of the Socialist Party, Hector Rodriguez, the election board said.

And Chavez's younger brother, Argenis Chavez, held the rural state of Barinas, where the family comes from.

'UNBELIEVABLE, INEXPLICABLE'

The ruling Socialist Party previously controlled 20 of the 23 state governorships. But opinion polls had shown the opposition set to upend that, given voter anger at hunger and shortages stemming from an economic meltdown.

The opposition's five wins were two more than they took in the 2012 gubernatorial race, but far below the 18-19 they had targeted. "These results are unbelievable and inexplicable," opposition spokesman Ramon Aveledo said.

The surprise results raised the prospect of more unrest in Venezuela, where four months of opposition-led protests earlier this year led to 125 deaths, thousands of arrests and injuries, and widespread destruction of property.

They also risked heightening foreign opprobrium of Maduro, whom various nations have labeled a "dictator".

U.S. President Donald Trump has already imposed some sanctions on Maduro and his senior officials, and has warned tougher measures could be in the offing. The European Union is also considering sanctions on Venezuela's government.

The opposition is highly unlikely now to return to a stuttering dialogue process with the government begun last month in the Dominican Republic.

"If we believe in basic mathematics and pay attention to the nationwide discontent in Venezuela, this vote shows that the regime feels very comfortable rigging elections to stay in power," said analyst Raul Gallegos, of Control Risks.

"This is a regime that now fears no one."

During the gubernatorial election campaign, the government made liberal use of state resources in its candidates' campaigns, evoked popular former leader Chavez at every rally, and appealed to Venezuelans' exhaustion with political turmoil to vote against "candidates of violence."

'VOTE FOR PEACE'

"I vote because I want peace, not terrorism," customs official Franquelsi Anciana said, casting a vote for the government candidate in western Maracaibo city.

Maduro has said all governors, including the five new opposition ones, must swear allegiance to the controversial new Constituent Assembly superbody elected in July.

But the opposition does not recognize the entirely pro-government body, which supersedes all other institutions, including the opposition-controlled congress.

The election board put up various hurdles for the opposition. Those included the relocation of 273 voting centers on security grounds - mostly away from pro-opposition areas - and a refusal to update the ballot to remove names of opposition politicians who lost in primaries, confusing voters.

There were also technical glitches such as electrical failures - which have become commonplace in the crisis-hit economy - although the government said these were minimal.

Turnout was more than 61 percent.

"I used to have enough food in my house to feed my children tomorrow, but now no longer. Hunger motivates us to vote," said Zulay Acosta, voting early in southern Puerto Ordaz city.

The government cast Sunday's votes, from remote Amazon and Andean communities to heavily populated Caribbean coastal areas, as evidence Venezuela is no dictatorship, contrary to increased global criticism this year.

Officials also presented the poll as a vote against Trump.

Some opposition supporters, particularly youths in a self-styled "Resistance" movement on the front line of street battles earlier this year, had accused their leaders of selling out and legitimizing a dictator by even taking part in Sunday's vote.