Attackers on a motorcycle threw an explosive device, possibly a hand grenade, at the French embassy in central Athens, wounding a security guard, police said on Thursday.
However, no one claimed responsibility for the attack on the building opposite parliament, in one of Athens’s best-guarded areas.
The attack occurred less than a week before U.S. President Barack Obama visits Greece from November 15 to 16.
“It was probably a hand grenade, the building was not damaged but one officer there was slightly injured,” the official said.
Government spokesman Dimitris Tzanakopoulos said Greek police would carry out their duty to identify the perpetrators and guarantee the protection of all citizens.
Another police official said that the attackers were riding a motorcycle, according to footage from security cameras.
Small-scale attacks on businesses, police, politicians and embassies are frequent in Greece, with its long history of political violence.
Left-wing urban guerrilla groups often claim responsibility.
Also the Greece finance ministry, close to parliament, was evacuated on Thursday following a bomb threat which turned to be a hoax.