Tehran, June 25 (IANS) At least Three Iranian security guards were killed in an attack on a police car in west Iran bordering Iraq, media reported Wednesday. "In a terrorist attack in Salas Babajani region of Kermanshah province last night, Three police guards were killed," Xinhua quoted Shahriar Heidari, a provincial security official, as telling Fars news agency Wednesday. An unnamed police official denied that the attackers were Iraqi Sunni militants who might have crossed Iran's border. Following the recent developments in Iraq, Iranian officials said the Islamic republic has boosted security along its borders with Iraq.