Police clashed with radicals in Central Zurich (Representational image). (Associated Press)

Police fired tear gas and water cannon in central Zurich late Friday to disperse some 200 masked radicals who attacked officers and set cars, trees and trash bins on fire, sending terrified residents fleeing in the upscale and normally tranquil neighbourhood.The rioters, many of them armed with iron bars, threw rocks and Molotov cocktails at police in a rampage that left hundreds of thousands of euros worth of damage and that police said was claimed by left-wing radicals.The marauders gathered around 10:00 pm, hurling rocks at police officers, setting a police vehicle on fire and stealing law enforcement equipment before reinforcements arrived, the local police said in a statement.Trees, cars and trash bins on the streets were set ablaze by the hooligans, who also shattered storefronts and the window of a crowded restaurant, sending terrified diners fleeing to the basement and the back of the eatery.Seven officers were injured as a result of the unrest before police managed to restore order around midnight."Many of them were armed with iron bars, some wore masks and gas masks and protective clothing," the police said in a statement.Four men -- two Swiss, and nationals of Britain and Liechtenstein -- have been arrested on suspicion of participating in the unrest.

Zurich, Switzerland's largest city, is a major financial hub hosting numerous banking giants and is one of Europe's wealthiest cities.