BAGHDAD  - Bomb attacks in Baghdad and north Iraq on Tuesday killed six people, including an army colonel and three schoolboys, security officials said, a day after a spate of violence left 17 dead. In the disputed town of Saadiyah, Diyala province, Colonel Hassan Ali was killed when a roadside bomb struck the convoy he was travelling in, Saadiyah mayor Ahmed al-Zarkushi and a provincial security command centre official said. Three of Ali's bodyguards were wounded in the 5:00 am (0200 GMT) attack in Saadiyah, which lies in a tract of disputed territory claimed by both the central government in Baghdad and Iraq's autonomous Kurdish region.