Greek police say a powerful blast outside a closed nightclub in Athens is the second attack in the past two days linked to criminal extortion groups, PressTV reported.
The blast, which caused no injuries, occurred before 4 a.m. Friday near Athens City Center.
The explosion was so huge that it was heard across southern Athens and severely damaged the club's frontage, AP reported.
Police say extortionists, who have carried out several similar attacks in recent years, are responsible for the attack.
On Thursday morning, another bomb exploded outside a court in Athens City Center after an anonymous phone threat gave police the chance to evacuate the area.
The blast, which occurred 40 minutes after a warning to a newspaper and private TV station, gave authorities time to evacuate nearby buildings.
According to reports, the explosive device had been placed on a motorbike in front of the building.
The blast damaged two administrative court buildings in central Athens, shattered windows and damaged cars and sent up a cloud of smoke that was visible across the city.