Parcel bombs have exploded at the Swiss and Russian embassies in the Greek capital Athens and several suspicious packages have been destroyed.
A suspected bomb was destroyed at the Bulgarian embassy and another, posted to the Chilean embassy, in a van.
No-one was hurt in the blasts, which came a day after four parcel bombs were found in the city.
The BBC's Malcolm Brabant in Athens says it appears to be a co-ordinated attack by an extreme left-wing group.
The first explosion happened at the Swiss embassy.
First reports said the device had been thrown into a courtyard, but police later said it had been left at the embassy's entrance.
"When the external packaging was removed, the contents burst into flames," a police spokesman said.
Bomb squad officials were on their way to the Russian embassy when the device there exploded.
The Bulgarian embassy was sealed off as experts carried out a controlled explosion on a suspected parcel bomb.
Another suspected device addressed to the Chilean embassy was found in a delivery van outside the Greek parliament and destroyed.
The courier carrying the parcel was worried and alerted police on guard outside the building.
Officials said another suspected bomb was intercepted at the offices of a courier company addressed to the German embassy.
BBC News
