The home of Germany's ambassador to Greece has been sprayed with gunfire from automatic weapons in a suspected "terrorist" attack, the government said.
Anti-terrorism police recovered more than 60 bullet casings from the official residence of Ambassador Wolfgang Dold following Monday's pre-dawn attack.
The government has said the attack was intended to hurt the country's reputation before it assumes the presidency of the European Union between January 1 and June 30.
"The Greek government expresses its outrage and outright condemnation of today's cowardly terrorist action which had the only apparent and objective of (damaging) Greece's image abroad. The perpetrators will soon be brought to justice," a Foreign Ministry statement said.
Dold, who has three children, thanked the Greek government for the police's "swift response.''
"To those responsible for this action, I state it will not affect the close and friendly relations between our two countries, and it will not reverse the country's economic recovery,'' he said in a statement.
Anti-terrorism police cordoned off streets around the residence located in the Halandri area of Athens.
No one has claimed responsibility for the attack. But police briefly detained and questioned six people before releasing them without charges.
Investigators are reviewing video surveillance cameras and are examining a stolen car found near the scene of the shooting, according to police.
Germany, as lead bailout lender, is often heavily criticised in Greece as the country suffers through its sixth year of recession and tough austerity measures enforced by Germany in return for the country's $330m bailout.
The left-wing November 17 group claimed responsibility for an attack on the same building in 1999.
Foreign diplomats were repeatedly targeted by far-left groups active from the mid-1970s, but such attacks have been rare since a major police crackdown on radical groups that has led to arrests and convictions.
Prime Minister Antonis Samaras and his foreign minister telephoned the ambassador following Monday's attack.
No one was hurt in the shooting.