Greek police said they arrested two suspects carrying a parcel bomb addressed to French President Nicolas Sarkozy on Monday, after a similar package exploded earlier at a courier company in Athens.
Officials said they arrested two Greek men, aged 22 and 24, in central Athens after finding two explosive devices in their possession. One of the explosive devices was addressed to the French president, police said.
Police were also investigating parcels addressed to the embassies of Mexico, Belgium and the Netherlands.
The package addressed to the embassy of Mexico exploded in Athens Monday, injuring a female employee at a courier company. The others were detonated by police.
The woman was taken to hospital with minor burns to her hands.
The two suspects arrested by police were both carrying handguns and wearing bullet-proof vests.
Reports said police believe there is no link with Al Qaeda and that the two men arrested were suspected to be linked to the Greek far-left militant group known as Fire Conspiracy Cells.
Greece has been plagued by a wave of bomb and gas cannister attacks by far-left and militant groups since the police killing of a teenager in Athens in December 2008 which sparked the worst riots the country has seen in decades.
Earlier this year a senior official at the country's public order ministry was killed in a letter-bomb blast which was addressed to the minister.