Shortly before sunrise on Friday, an anti-tank missile ripped through the U.S. embassy in Athens, rocking the compound but causing no injuries.
The rocket, apparently fired from more than 300 yards away across a busy boulevard and over a ten-foot security wall, smashed the glass front of the building and wrecked facilities near the U.S. ambassador's office on the third floor.
Investigators said they were gathering debris from the Russian-made, 45-cm-long missile that hit the heavily guarded building on top of the soaring U.S. seal on the embassy facade.
"We have yet to locate the staging area of this rocket attack," said Assimakis Golfas, the head police chief of the greater Athens area. "We are scouring the region, mainly buildings across the [street from the] embassy."
Public Order Minister Vyron Polydoras said the attack bore the hallmarks of a local, rather than foreign, terrorist group.
He said an anonymous person, claiming to be a member of the Revolutionary Struggle terror group, made at least two telephone calls to a local security company to assume responsibility for attack that rocked the Greek capital at 5:58 local time.
"We're investigating whether this claim [of responsibility] is in fact true," Mr. Polydoras told reporters after meeting the U.S. ambassador and visiting the site of the attack.
Revolutionary Struggle, a shadowy extremist group with Marxist leanings and strong anti-American sentiments, emerged from obscurity in 2003 with the bombing of an Athens courthouse complex. It has since carried out six attacks, including the near-fatal assassination attempt against Greece's culture minister, George Voulgarakis, last May.
The group remains the most active Greek terror organization since authorities broke up the country's most deadly urban guerrilla group, November 17, blamed for dozens of bomb attacks and for the killing of 23 people including American, British and Turkish officials. The leftist group was dismantled in 2002 as Greece cracked down in the run-up to the 2004 Olympics. Its suspected leader and other leading figures have been imprisoned in Greece's maximum security prison since 2003. More recently, however, a string of copycat terror cells have emerged, targeting government buildings and foreign business interests.
Friday's hit against the U.S. mission was not unprecedented. Eleven years ago, unidentified assailants fired a rocket into the embassy compound, damaging three diplomatic vehicles. No group claimed responsibility, but American officials blamed November 17.
Charles Reis, the U.S. ambassador, said the embassy neither suspected nor had been warned of a pending attack. "We can't speculate who's behind this," Reis told reporters. "Still, [we] treat it as a very serious attack. There can be no justification for such a senseless act of violence."