A small makeshift bomb exploded at a Greek courier company in Athens on Sunday, smashing windows but causing no injuries, a Reuters witness and police officials said.
The explosion damaged some vehicles parked outside the local firm and caused minor damage to several neighboring buildings. Police officials said the bomb consisted of at least five gas canisters and some explosive material.
Gas canister attacks against businesses and police are frequent in Greece. Small bomb attacks against politicians have risen since the country adopted harsh and deeply unpopular austerity measures under the terms of two successive bailouts by the European Union and the International Monetary Fund.
In January, two Greek anarchist groups claimed responsibility for an explosion at an Athens shopping center that fuelled fears of rising political violence.
That incident followed a series of small homemade bomb attacks on journalists and political figures.
Less than a week before the mall blast, unknown gunmen fired shots at the Athens offices of the New Democracy party, which heads the governing coalition. There were no injuries and no claim of responsibility for the attack.