Riot police clashed with angry protesters today as this year's May Day demonstration erupted into predictable chaos in London.
More than 5,000 protesters packed the city's streets and were involved in a series of skirmishes with baton-wielding officers throughout the afternoon.
Blood-soaked demonstrators were taken to hospitals and at least one police horse was injured during the street battles.
Fifteen activists, masked by balaclavas, stormed into a Sainsbury's store in central London screaming anti-capitalist chants while others hurled concrete slabs at police.
More than 35 demonstrators were arrested, many for possessing weapons including lock-knives and screwdrivers.
Schools and a library in Westminster were closed and dozens of businesses lost millions of pounds after being forced to shut.
The scenes in London mirrored similar protests across the world, including Berlin where bonfires were lit on the streets and barricades erected to fend off police.
Scotland Yard tonight admitted officers temporarily lost control of the crowds after protesters managed to break through police lines in Oxford Street at about 4 p.m.
Officers exchanged blows with demonstrators at several points around Oxford Circus as any hopes that the day would remain calm evaporated.
By 5 p.m., 29 people had been arrested, including eight from Denmark, Poland, Belgium and the USA, Scotland Yard said.
The protests, under a broad banner of anti-capitalism, began peacefully with mass cycle rides and chanting.
But the atmosphere turned sour after a large group gathered in Oxford Street at the climax of what the organisers called a game of May Day Monopoly, based on the locations in the board game.
Police in riot gear moved in to contain the demonstrators and prevent any looting of stores on London's main shopping street.
Several bridges across the Thames were closed to pedestrians in an attempt to prevent more demonstrators converging on the city.
At one stage demonstrators staged a sit-down protest outside the Niketown store and H&M at Oxford Circus.
The carnival atmosphere of the morning gave way when protesters surged forward towards police lines - crushing several people.
Officers came under a hail of wine bottles, beer bottles and sticks as demonstrators attempted to surge forward into Regent Street.
One man was seen being led away with blood pouring from his head while police videoed and photographed protesters.
PA