ATHENS, Greece, June 17, SPA -- Gunmen shot dead an anti-terrorist police officer guarding a witness in central Athens earlyWednesday, in an escalation of domestic terrorist attacksin the country. Police spokesman Panagiotis Stathis was quoted as saying by The Associated Press that between 15 and 20 shots were fired at the officer by at least three gunmen at about 6:20 a.m. (0320 GMT) in the residential district of Patisia. «It was a cold-blooded murderous attack,» said Stathis,adding that the attack was not preceded by any warning calland that there had been no immediate claim ofresponsibility.--SPA www.spa.gov.sa/675446