Attackers on a motorbike threw a hand grenade at the Russian consulate in Athens on March 22, causing minor damage but no injuries.
There was no immediate claim of responsibility for the early morning attack on the consulate in the suburb of Chalandri. Police cordoned off the area and sent a bomb disposal team to the consulate.
The device exploded beneath a security guard booth but was thought to be a low-density explosive.
Police sources said they suspect the attack was carried out by a leftist militant group called the Popular Fighters Group.
The group claimed responsibility for a bombing against the offices of a TV station and newspaper in December.
The Greek Foreign Ministry said it "unreservedly condemned" the attack.
In 2016, a security guard was wounded in a similar incident at the French embassy in central Athens.
Grenade Thrown At Russian Consulate In Greece; No Injuries Reported