A Greek extremist group claimed responsibility for bomb attacks in the run-up to the Olympic Games and issued a veiled threat against visitors to the summer sporting extravaganza. The warning from the Revolutionary Struggle came after makeshift bombs exploded at a Greek bank in an Athens surburb early Thursday, and another explosive device was found at a nearby British bank. The blasts, which caused some damage but no injuries, came eight days after dynamite explosions at a police station in Athens, an incident blamed on local extremists rather than international terror groups like Al-Qaeda.Full Story