TINOS – The 2004 Olympic Games still face a potential threat from terrorists despite a recent police crackdown on a deadly Greek urban guerrilla group, a top security adviser said yesterday. Police have arrested 17 suspected members of the far-left November 17 militant organization following a bungled bomb attack on June 29. The group has killed 23 people, including four American officials. «They’ve made significant inroads into November 17, but the important thing is to always bear in mind that urban terrorism can spring up at any time,» said Peter Ryan, a 2004 security adviser. «Because one terrorist group is out of the way that doesn’t mean to say you dismiss that threat coming from another quarter,» Ryan said at a two-day meeting with journalists on this Aegean island. Athens organizers have budgeted a record $600 million for Olympic security. Athens is receiving counterterrorism advice from Australia, Britain, France, Germany, Israel, Spain and the USA. Each of these countries will offer up one area of expertise to assist the Greek police, Ryan said. «We are pretty much on track,» he said. «We’re pretty well there, but nonetheless it’s a huge task.» A former Australian police official, Ryan said that Olympics officials and the Greek police are planning for «the unthinkable» after last year’s Sept. 11 attacks on the USA. «When I say all threats, I mean all threats,» he said. Ryan said a flight-exclusion area will be set up around the capital during the Games. Because of Greece’s location, its porous land and borders will also be heavily secured, he said. Some 45,000 security personnel will work at the Olympics: 25,000 from the police, 7,000 from the military, 3,000 coast guards, 1,500 firefighters, 5,000 private security contractors and 5,000 trained volunteers. Ryan said there are usually sympathizers and supporters of terrorist groups that may not get caught, and it is not easy to know when and if they will act.