LISBON (Reuters) -Thousands celebrated the 50th anniversary on Thursday of Portugal's "Carnation Revolution" that toppled the longest fascist dictatorship in Europe and ushered in democracy, though support for the far right has revived in recent years.

Antonio Oliveira Salazar ruled Portugal from 1932 to 1968, but the arch-conservative, authoritarian regime lasted for a further six years under his successor Marcelo Caetano, only crumbling on April 25, 1974.

The almost bloodless revolution was conducted by a group of junior army officers who wanted democracy and to put an end to long-running wars against independence movements in African colonies. The military coup by the "Captains of April" group brought about rapid decolonisation.

Thursday's celebrations kicked off in Lisbon's Commerce Square on the edge of the River Tagus where two frigates sat moored as military vehicles and more than 400 soldiers paraded by, singing the national anthem as fighter jets roared overhead.

Thousands of people turned out to cheer the parade. One of them, 74-year-old Joao Marcelino said the recent "very strong" rise of the populist far right in Portugal, echoing trends elsewhere within the 27-nation European Union, was worrying because it "does not bring good solutions for any country".

"I'm worried that, after 50 years of democracy, people are not enlightened...but the far right is advancing because the mainstream parties are not developing our country," he said.

Though its multi-party democracy has proven stable and the country's infrastructure has been greatly modernised since 1974, aided by EU membership and development funds, Portugal remains Western Europe's poorest state.

Discontent over a housing crisis unleashed by steadily rising rents has boosted the far right, as have low wages, sagging healthcare and cases of alleged corruption involving the mainstream parties.

Lisbon University political scientist Antonio Costa Pinto said that while most Portuguese embrace liberal democracy and are proud of the April 25 revolution, the growing popularity of the populist, anti-immigration Chega was the "elephant in the room" at this year's Carnation Revolution celebrations.

"Chega attracts those who have a revisionist view of history with the idea that colonialism and the empire were not bad, and that the glorious Portuguese past and its symbols should be valued," Costa Pinto said.

Chega makes frequent public use of Salazar's motto "God, patriotism and family", to which the party has added "work".

Chega leader Andre Ventura has denied that he or his party is fascist, while being anti-establishment and wanting to change Portugal's constitution.

"Fifty years ago we had a revolution that gave us freedom, but along the way our dignity was taken away from us," Ventura told parliament on Thursday, accusing the ruling Social Democrats and main opposition Socialists of failing to end poverty.

Founded in 2019, Chega is Portugal's third largest party, having quadrupled its cohort of lawmakers to 50 in March's parliamentary election.

(Reporting by Sergio Goncalves, editing by Aislinn Laing and Mark Heinrich)

By Sergio Goncalves and Miguel Pereira