The head of Venezuela's opposition-controlled congress was pulled from his car and briefly detained on Sunday after he stepped up a campaign to oust the country's unpopular president, Nicolas Maduro.

"Sebin detains Juan Guaido," Guaido's wife tweeted, referring to the state intelligence services. The arrest was confirmed by other lawmakers who were waiting for him at the meeting in the town of Caraballeda.

She later posted another message vowing that "the dictatorship will never subdue his [Guaido's] fighting spirit."

A video circulating on social media showed an SUV being intercepted on a highway in which Guaido was purportedly traveling.

Read more: Opinion: Venezuela's Nicolas Maduro has lost all legitimacy

Later, a member of his party speaking on the condition of anonymity out of fear for their safety said he was subsequently released.

Maduro stays put, for now

Guaido has been leading an increasingly tense standoff with Maduro in an effort to oust the socialist president from power. Maduro was sworn in for a second six-year term on Thursday, after winning a May 2018 election widely boycotted by the opposition and condemned as rigged by governments around the world.

Maduro insists it was fair and that opposition leaders did not take part because they knew they would lose. The president has accused Washington of encouraging a coup d'etat against him.

At a rally on Friday, Guaido said he was prepared to take over as interim president, but only if the army supported the move.

Read more: Former Venezuelan Supreme Court judge flees to US, denounces Nicolas Maduro

Guaido, a lawmaker from the hardline Popular Will opposition party, was elected to head the National Assembly on January 5.

However, the assembly has been stripped of powers by the Supreme Court and a pro-Maduro legislature known as the Constituent Assembly, which helps prop up his government.

The US State Department on Saturday called for an "orderly transition" to a new government, in its most specific call yet for a change of leadership in the crisis-torn country. Maduro has presided over a virtual economic collapse in what was once Latin America's wealthiest nation.

The US, the European Union, Canada, and 12 Latin American countries have said they do not recognize Maduro's re-election.

mm/jm (AFP, AP, Reuters)

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