Gun and bomb attacks in Baghdad and north Iraq on Tuesday killed eight 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.

In another roadside bomb attack in the village of Yathreb, in Salaheddin province around 70 kilometres (45 miles) north of the capital, three boys aged between nine and 11 years old were killed while going to school, a police officer and a medic at nearby Balad hospital said.

Two officials working for the agriculture ministry were killed by a magnetic "sticky bomb" attached to their car while headed to work in the town of Al-Sharqat, also in Salaheddin 290 kilometres (180 miles) northwest of Baghdad, local police and a security official said.

And in the main northern city of Mosul, two Iraqi army soldiers were killed when gunmen opened fire on their checkpoint Tuesday evening, according to army First Lieutenant Mohammed al-Juburi and a police officer who declined to be identified.

The violence struck a day after attacks across Iraq, many of which targeted Shiites, killed 17 people and wounded dozens.

Tuesday's unrest comes amid a political standoff in Iraq pitting the Shiite-led government against the main Sunni-backed political bloc, stoking sectarian tensions.