ATHENS - Thousands of police cordonned off streets across central Athens Sunday as a military parade to mark Independence Day was held under unprecedented security measures for fear of anti-austerity protests.

For the first time, the public was banned from a large part of the route, including the area in front of Parliament from where politicians and other officials will watch the march.

Police, including hundreds in riot gear, cordonned off streets leading to the parade route, allowing only access to those with special invitation. Low-hanging fruit from bitter orange trees that line the city's pavements had been picked ahead of the march -- apparently to prevent them from being thrown by protesters. The oranges, which are inedible except if made into jam, have become a favourite projectile during demonstrations.

Usually, thousands of people line the main streets of central Athens to watch the March 25 military parade, which marks Greece's uprising against the Ottoman Empire in 1821.

But public anger has grown as the government has imposed yet more spending cuts and tax hikes during a severe financial crisis. On another national day last October, the country's figurehead president was heckled and a similar parade called off due to protests.

Since then, politicians have frequently fallen victim to angry groups shouting insults or throwing yogurt or eggs at them during public appearances across the country.

As Sunday's ceremonies got underway with President Karolos Papoulias laying a wreath at the Tomb of the Unknown Soldier and a military band playing the national anthem, a group of about a dozen people at the bottom of Syntagma Square across a main street from the legislative building chanted "Traitors."

They were quickly surrounded by riot police and gradually dispersed, with the parade ending without further incident.

"Look at what we've come to," said Nikolas Blezas, one of the protesters, holding up a picture of one of Greece's revolution heroes. "It's as if we are living under who knows what kind of regime. I can't take it."

Police said 27 people were detained in various areas of Athens and three were arrested, one for carrying a flare and two for throwing eggs at a student parade in the seaside suburb of Glyfada.

The country's wounded war veterans boycotted this year's parade for the first time, objecting to austerity measures that have seen salaries and pensions cut and taxes repeatedly raised.

Armoured vehicles and military aircraft flyovers have not been carried out at the parades since 2010, when the government stopped the practice as part of cost-cutting measures.

The values of "bravery, sacrifice and faith" of those who fought in the Greek revolution "show us the path with which we can win today's national battle to rebuild our economy," Prime Minister Lucas Papademos said after the parade.

An Independence Day parade by schoolchildren on Saturday was also held under draconian security measures, with police blocking off a large area of the route to pedestrians. Members of the public, including the children's parents, were able to watch the parade only after it had passed in front of Parliament.

Security was also increased for parades in other cities across the country, while some municipalities decided to break with tradition and not set up stands for local politicians to watch the parades.

In the northern city of Thessaloniki, cordons of police kept about 500 protesters away from a parade by schoolchildren, with minor scuffles in which demonstrators threw eggs, coffee and plastic bottles of water at police. Authorities said 25 people were detained, while local media also reported scuffles between protesters and police in the western port city of Patras.

In Iraklio, on the island of Crete, a student parade was cancelled after protesters moved against officials. Police used tear gas and pepper spray on the protesters, who staged a parade of their own.

This year's Independence Day comes as Greece's government pushes through final parts of legislation needed to secure the country's second multibillion dollar international bailout, from which it began receiving funds last week. The rescue loans from other eurozone countries and the International Monetary Fund are essential for the country to avoid a potentially disastrous bankruptcy.

Once the legislation is passed, the current coalition government is to declare general elections, most likely to be held in early May or late April.