Greek police fired teargas to disperse dozens of protesters who hurled petrol bombs at police and set alight cars and garbage containers in central Athens late on Tuesday, police officials said.
The clashes erupted after a march in support of a self-proclaimed anarchist, who was sentenced to prison on robbery charges in October, and has been prevented from attending university classes. Nikos Romanos, 21, has been on hunger strike since Nov. 10 and is hospitalized.
Police said that some shops, three cars and one bus were damaged during the violence which broke out four days before the anniversary of the 2008 police killing of a teenager that led to the country's worst riots in years.
Calm later returned to the bohemian Exarchia neighborhood, which is closely guarded by police and where riots have often broken out in the past.