Police in Budapest used water cannon and tear gas to attempt to disperse several hundred far-right protesters Monday night.

Supporters of the far-right Hungarian Self-Defense Movement were trying to reach the Hungarian State Opera, where Socialist Prime Minister Ferenc Gyurcsany was due to give the keynote speech at a gala event commemorating the 1956 anti-Soviet revolution.

A Reuters press photographer suffered head injuries when he was hit by a bottle thrown by the protesters. Several ambulances were in the Oktogon area of Pest, a few blocks from the Opera, where the most serious clashes were taking place.

Emergency service officials said at least five people — including two other photographers from Hungarian newspapers — had been treated for injuries, none thought to be serious, and taken to local hospitals.

Protesters — estimated by police to number as many 1,500 — pelted police in riot gear with Molotov cocktails, bottles, rocks, and cans and also overturned several cars to form a barricade.

The gala event in the Opera began as scheduled and Gyurcsany was holding his speech while the clashes took place nearby.

Police had banned a 1-kilometer march planned by the Hungarian Self-Defense Movement from a rally they held on Szabadsag ter (Freedom Square) to the Opera, but hundreds of protesters attempted to walk the route anyway.

"We can either wait until 2010 or take our own fate in our hands," an unidentified member of the far-right group told the crowd before they headed toward the Opera. Parliamentary elections are scheduled to be held in mid-2010.

Police sealed off several blocks around the Opera and residents of the area were allowed in only after their ID was checked.

Police issued a statement shortly before 1800 GMT saying that they were using force to restore public order and asked citizens to avoid going near the downtown area where the clashes were taking place.

Police denied media reports saying they had used rubber bullets to disperse the crowds and said they were able to successfully disband the protest.

Some 120 commemorative and protest events were scheduled to be held in the Hungarian capital between Sunday and Tuesday, the official anniversary of the start of 1956 uprising.

Hundreds were injured during a police crackdown on similar protests around this time last year.

Hungary has been in a state of political upheaval since last September, when state radio broadcast parts of a secret speech by Gyurcsany in which he acknowledged lying about the economy to win the April 2006 parliamentary elections.

Since then, Gyurcsany's popularity has dwindled amid economic austerity measures introduced to cut Hungary's state budget deficit, the largest in the European Union in the past few years.

According to the latest polls, support for Fidesz, the main center-right opposition party, stands at around 40 percent, while the Socialists are at 20 percent, with about 75 percent of voters saying the country is headed in the wrong direction.