A Greek militant group threatened in a statement published Thursday to continue its bombing campaign, saying recent attacks against Citibank were in response to the international financial crisis.

The Pontiki weekly newspaper published a statement from the Revolutionary Struggle group, which claimed responsibility for a failed car-bomb attack Feb. 18 on Citibank offices in Athens and a bomb attack Monday on a suburban Citibank branch that caused damage but no injuries.

Authorities did not immediately comment on the statement but they have not questioned its authenticity. The newspaper has been used by the militant group in the past to publish proclamations.

In the Feb. 18 attack, a stolen car was found packed with explosives outside Citibank offices north of the Greek capital. But the time-bomb -- considered powerful enough to destroy the four-story building -- failed to detonate.

In the statement, the militant group argued the American bank is part of a "criminal network of international capital" responsible for the financial crisis. It said the bomb contained 125 kilograms (276 pounds) of explosives.

The group said it had tried to warn authorities to avoid casualties by telephoning a newspaper. Police did not say they had received a warning.

Revolutionary Struggle has carried out more than a dozen bomb and shooting attacks since 2003, including the firing of a rocket-propelled grenade into the U.S. Embassy in Athens in 2007.

Greece considers the group a terrorist organization, and the U.S. government is offering $1 million for information that leads to the arrest of Revolutionary Struggle members in connection with the embassy attack.

The militant group vowed to continue to carry out time-bomb attacks against the country's "political and economic elite and the apparatus of capitalism and the state," and would issue warnings to the media.

Greece has faced attacks by domestic terrorists for decades, but major groups were broken up before the 2004 summer Olympics in Athens.

But new groups have appeared in recent years and attacks have increased this year following major riots in December over the police shooting of a teenage boy.

On Wednesday, a daily newspaper published a leaked police document detailing heightened security measures for possible terrorist targets, including many prominent journalists.

Four senior officers at the police's anti-terrorism division were suspended over the leak pending an investigation, authorities said.