The march follows daily protests in Athens and the second city of Thessaloniki over Grigoropoulos' death on December 6 which have regularly degenerated into violence.
Tension was also caused when another teenager, the son of a union leader, was wounded in a mysterious shooting incident on Wednesday night.
In the latest protest on Friday, masked youths smashed up the French cultural institute after students and VoteStrike activists marched in the western district of Peristeri to condemn the second shooting.
Greek Farmers Block Bulgarian Border
The main border checkpoint between Bulgaria and Greece is blocked again, due to protests of Greek farmers 10 kilometers down south, the Bulgarian police from the region of Blagoevgrad announced Saturday.
The border checkpoint has been either blocked or closed for most of the week, as protests in Greece show no signs of calming down. The Greek farmers are protesting against low retail prices and no subsidies in a time when production prices are on the rise.
A group of masked men broke into the building housing the offices of Tiresias SA, a company that keeps records of delinquent debtors and cardholders, and firebombed the company's offices.
In the northern city of Thessaloniki, a small group of self-styled anarchists occupied a movie theater in the city's main square and threw cakes and candy at Mayor Vassilis Papageorgopoulos and one of his deputies. The mayor was attending a Christmas-related event distributing the sweets to children with sickle-cell anemia when the rioters seized the stand and threw its contents at the city officials.
Chanting "One day a year for the sick and the orphaned but billions of euros for the banks".
The Christmas tree protest had been call to action as part of a day of events in Greece and around the world exactly two weeks since Grigoropoulos' shooting.
Police said about 1,000 riot police used pepper spray on the protesters and later charged them and cleared the square. At least three news photographers were injured by police wielding batons. The tree survived the attack.
The square's first Christmas tree was burned to the ground on Dec. 8, the worst day of rioting in Athens' center.
RUSSIA- Riot police beat protestors
Riot police clubbed, kicked and detained dozens in the Pacific port of Vladivostok on Sunday in a violent crackdown on a peaceful protest that was one of dozens across Russia by people outraged over an increase in car import tariffs.
Many Russians say they have a right to buy what they want without paying to support the Russian auto industry.
With unemployment spiking, prices rising and the ruble sliding, the protests over a seemingly mundane tariff appear to be broadening into a wide expression of public discontent--and beginning to present a genuine challenge to the Kremlin.
