Blast rips through U.S. embassy compound in Athens.

ATHENS (Reuters) - An explosion ripped through the U.S. embassy compound in central Athens on Friday, a police source said.

It was not clear what caused the blast and there was no immediate word on whether there were any casualties. Police cordoned off all roads around the embassy.

Police officials at the scene said that whatever caused the explosion damaged the official embassy sign outside the mission, but there was little other indication of the extent of damage inside.

UPDATE at 1/12/07 8:09:04 am:

The Associated Press is skeptical that firing an anti-tank rocket at a US embassy is “terrorism:” Blast at U.S. embassy called ‘terrorism’.

ATHENS, Greece - A rocket struck the U.S. Embassy early Friday, exploding inside the modern, glass-fronted building and shattering hopes that Greece’s leftist anti-American militant networks had been dismantled.

Greek authorities said the attack, which caused no injuries, was probably carried out by a domestic terrorist group.

The small anti-tank missile, fired from across a six-lane boulevard, narrowly missed the large blue-and-white U.S. seal on the embassy’s facade and the ambassador’s office, and pierced the building above the front entrance shortly before 6 a.m. It damaged a third-floor bathroom and shattered windows in nearby buildings.

“There were no injuries and very minimal damage,” U.S. Ambassador Charles Ries said outside the embassy.