Hopes for a show of national unity to mark the 1956 uprising were ruined by rubber bullets, teargas, water cannon and street-fighting across the city centre. At least 40 people were injured, including several policemen, and 40 were arrested.

The clashes were profoundly embarrassing for the Socialist-Liberal coalition Government, which had spent months planning a series of elaborate commemoration ceremonies to mark the sensitive anniversary.

Hundreds of police in full riot gear, some wearing ski-masks, advanced on anti-government protesters, some of whom were bent on disrupting official ceremonies at the parliament building. Demonstrators, many with scarves wrapped around their faces, taunted the lines of police. Some demonstrators broke up rocks ready to hurl at the police, or carried staves.

Police helicopters swooped low over the demonstrators and squads of police moved forward in military formation as the clouds of teargas floated past the entrances of city- centre five-star hotels. There were loud cheers when some protesters took control of a Soviet-era T34 tank that had been parked on the street as part of the commemoration ceremonies, and drove it at police lines, provoking a further fusillade of teargas. But the tank ran out of fuel.

Late last night police used trucks to run over barricades erected by several hundred demonstrators on the Elizabeth bridge over the River Danube.

There is widespread anger that the commemoration of the uprising, for many the proudest moment in Hungarian history, has been led by Ferenc Gyurcsány, the Prime Minister, 45, who was a youth leader in the Communist Party — the party that helped the Soviet Union to crush the uprising. “The Socialists are the descendants of the Communists. They helped themselves to the nation’s riches. Gyurcsány admitted that he lied and he should step down,” Marta Toth, a 45-year-old housewife, said.

The violence echoes the disturbances of a month ago when protesters stormed the television station after a tape of Mr Gyurcsány admitting that he had lied to win elections in April was leaked to the media.

Some of those fighting the police were supporters of the opposition Fidesz party, who have been demonstrating every day since the tape was leaked. Others were far-right extremists, equally opposed to the Socialist Government.

Maria Kiss, 36, a management consultant, said: “It was a peaceful demonstration, then everyone started shouting that the police were firing teargas and rubber bullets. We have had enough of Gyurcsány and the lies. It is ridiculous that the Socialists are celebrating 1956 when the Prime Minister does not dare to go out and give a speech. He should resign.”

The ceremony outside parliament yesterday morning, when international dignitaries laid flowers at the 1956 memorial, was marred by crowds of protesters shouting “Out with Gyurcsány”, their chants clearly audible on the podium.

José Manuel Barroso, the European Commission President who was among those marking the occasion, said: “Hungary’s achievements over the past 16 years are substantial. The people have a great opportunity in their grasp.”

Tens of thousands of demonstrators gathered at Astoria, near the radio building where fighting first began in 1956, where Fidesz was holding a protest. Viktor Orban, the party leader, asked the demonstrators to refrain from violence but said that the Government was illegitimate.

Inside parliament the Prime Minister said that Hungarians in 1956 had no choice but to rebel, but the country, which held its first free elections in 1990 and joined the European Union in 2004, was now a modern, democratic state. “Despite the often justified disappointment and discontent, the majority of Hungarians believe that parliamentary democracy is the most suited to express people’s will,” he said.

TROUBLE BREWS

September 17: Ferenc Gyurcsány, the Prime Minister, admits to lying

September 18: Peaceful protests descend into riots

October 1: Mr Gyurcsány’s party suffers heavy losses in local elections

October 6: He wins a vote of confidence of MPs

October 20: A group of hardcore protesters remain outside Parliament

October 22: Opposition Fidesz party boycotts 50th anniversary celebrations

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