Athens:
A powerful bomb detonated outside a court building near central Athens on Thursday morning, causing significant damage but no injuries, the police said.
The authorities found the device and cordoned off the area around the Athens administrative court after calls to the private television station Alter and the daily newspaper Eleftherotypia at about 7:40 a.m. warned that a bomb would go off there in 40 minutes.
"In both cases, the caller said the device had been strapped to a scooter outside the courthouse and gave the scooter's registration number," said an officer at the Athens police headquarters who spoke on the condition of anonymity because he was not authorized to comment publicly. "The explosion occurred two minutes after the deadline," the officer said, adding that police bomb disposal experts had gathered the remnants of the device and the vehicle and were examining them.
A local resident told the private television station Skai that he had seen two men dressed in police uniforms pull up near the court building on a motorcycle about 6:30 a.m. The witness said he greeted the men, who told him they were abandoning the scooter because it had engine problems. According to the witness, the pair then got into a white van parked nearby and were driven away by a third person.
The explosion damaged the facade of the court building as well as several cars, and also blew out windows in nearby apartment buildings.
Justice Minister Haris Kastanidis, who visited the scene, said authorities "will not be intimidated by terrorist attacks."
"There is no need for verbal condemnation," he said. "We must simply continue with our job, using the methods we have been using."
Shortly before the bombing in Athens, a much smaller explosion occurred outside the Greek Embassy in Buenos Aires in the middle of the night.
"According to the initial findings of the Argentinean police, the blast was caused by a Molotov cocktail thrown by unidentified assailants," the Greek Foreign Ministry said in a statement, referring to a crude incendiary weapon comprising a glass bottle filled with flammable liquid. There were no injuries and minimal damage in that incident, the ministry said.
The officer at Athens police headquarters said it was too early to confirm the composition of the bomb that exploded at the courthouse, or to determine which of the several guerrilla organizations in Greece might have orchestrated the attack. He added that another anonymous call made to Eleftherotypia nearly an hour after the explosion had warned that a second bomb would go off at a tax office in southern Athens. By midday there had been no other explosion.
There was no immediate claim of responsibility for Thursday's attacks, which come a few weeks after a string of parcel bombs were sent to several foreign embassies in Athens, causing one injury and international alarm after one device reached the Berlin office of the German chancellor, Angela Merkel.
Two self-proclaimed members of a guerrilla group called Conspiracy of the Cells of Fire -- Panagiotis Argyrou, 22, and Gerasimos Tsakalos, 24, who are in detention pending trial on terrorism charges on Jan. 17 -- claimed responsibility for those attacks.
The Athens police officer said the trial of the two suspects was not scheduled to take place in the courthouse targeted by the bomb on Thursday.
Thursday's explosion also came three days after an Italian guerrilla group called the Informal Anarchist Federation, or F.A.I, claimed responsibility for a letter bomb that exploded at the Greek Embassy in Rome, injuring two people. In its claim, the Italian group said its attack had been staged to express solidarity with 17 suspected members of the Conspiracy of the Cells of Fire.
"Conspiracy's project, like ours, is based on the action and methods of revolutionary violence," the Italian group said in its claim.
The Greek and Italian police have increased their cooperation in recent months in a bid to crack down on anarchist groups in both countries that are believed to be sharing knowledge and tactics.