The bulk of the demonstration -- a general strike that paralyzed Greece as the two-thirds of the country that is still gainfully employed walked off the job Wednesday -- was peaceful. Tens of thousands marched on the national parliament early in the day to demand an end to the painful austerity measures being imposed on the populace as part of an international financial rescue, chanting slogans "EU, IMF Out!" and ""We won't submit to the troika."

Sometime in the afternoon, however, a contingent of masked activists around Athens' Syntagma Square clashed with riot police, the much-maligned AΣTYNOMIA paramilitary unit, and protesters began exchanging firebombs, teargas canisters and large rocks with the agents of the law.

As in previous demonstrations, gasoline bombs played a prominent role. A cameraman from international broadcaster Russia Today captured several instances of police officers yelling and flames on their uniforms being extinguished by colleagues. According to London's Guardian, an errant firebomb set alight a tree inside the country's "national garden."

While the percentage of protesters being unruly amounted only to a tiny percentage of the larger demonstration, it appeared at times the few dozen black-clad youths were keeping several hundred riot police officers in check. Photographs from Reuters show agents hiding behind shattered polycarbonate shields or throwing teargas canisters at protesters, who were themselves shown slinging rocks, Molotov cocktails and gas canisters back at the police.

Protests, although less confrontational in nature, also continued in Spain.