Guerrillas fire grenade at US embassy in Athens

An anti-tank rocket struck the US Embassy early yesterday morning, causing limited damage and no injuries, but reviving fears of a resurgence of far-left Greek militant groups that carried out deadly strikes over three decades.

The shoulder-fired missile narrowly missed a large blue-and-white US seal on the embassy's facade and damaged a third-floor bathroom near the ambassador's office.

US Ambassador Charles Ries called the attack "very serious" and said no warning had been given.

"There can be no justification for such a senseless act of violence," he told reporters outside the embassy. "The good news is no one was hurt and (there was) minimal damage."

Greek authorities blamed domestic militant groups that have carried out a spate of bombings against police and government buildings despite a crackdown of terrorism before the Athens Olympics in 2004.

Police are examining the authenticity of two calls claiming responsibility from the group Revolutionary Struggle, which has carried out six bombings since first appearing in 2003.

The shadowy group has criticized the United States in past statements, citing treatment of prisoners at the US military detention center in Guantanamo Bay, Cuba.

"It is very likely that this is the work of a domestic group," Public Order Vyron Polydoras said. "We believe this effort to revive terrorism is deplorable and will not succeed."

In Washington, State Department spokesman Sean McCormack said the United States also saw no early signs of international involvement. The Pentagon received a report on the attack, but no request for any action, a US military official said.

The embassy was struck shortly before 6am, and the blast shattered windows in nearby buildings. Commuter traffic in the downtown area came to a standstill for three hours as police cordoned off streets around the building to gather evidence - dusting cars for fingerprints and gathering discarded chewing gum and cigarette butts from the street.

The government said it was seeking permission from the courts to view traffic camera footage, officially excluded from the police investigation under strict Greek privacy laws.

Yesterday's attack resembled methods used by members of the terrorist group November 17 who had eluded police since 1975 until their eventual capture and then conviction in 2003.

But the type of weapon used has not been seen in previous Greek attacks: a 2.36-inch rocket, which police said was probably fired from an extendable Russian-made launcher.

Public opposition to US policies - and the invasion of Iraq in particular - has remained strong since Washington provided support for a 1967-74 military dictatorship.

Government and opposition party officials strongly condemned the attack, the third against the US Embassy since the mid-1970s.

"I ... express the solidarity of the Greek people following this deplorable action," Foreign Minister Dora Bakoyannis said.

State television said she had written to US Secretary of State Condoleezza Rice to promise full cooperation in efforts to find the attacker, but the conservative government was criticized in Greece over the attack at Athens' most heavily guarded site.

"How is such an attack on the American embassy possible, when the site is the No. 1 target in the country?" said Alekos Papadopoulos, spokesman for public order at the main opposition Socialist party. "This points to problems with the police's capabilities."