In southeast Baghdad, at least one civilian was killed and eight people were injured by another roadside bomb.
A truck was struck by the bomb in the early morning attack.
A third attack consisted of two co-ordinated explosions in the al Waziriyah district of northern Baghdad, police said.
The first explosion injured two civilians and a second killed one soldier and wounded six others, as they arrived at the scene.
The bombings follow a relative lull in attacks in the Irali capital in recent months, after a US troop "surge".
All types of attacks in Iraq have dropped by 55 per cent since the "surge" became fully operational in June, Gregory Smith, the US military spokesman, said.