Attack in southern district of Baghdad kills at least five policemen, reports say.
Another roadside bomb struck a minibus in eastern Baghdad, killing one person and wounding six others, a hospital source said.
No group has claimed responsibility for the attacks.
The blasts came a day after a roadside bomb targeted pilgrims on their way to Karbala, killing one and wounding four others.
Thursday’s pilgrimage was the second major religious gathering in Iraq since the withdrawal of US troops from urban centres on June 30.
Attacks by al-Qaeda remain common, raising doubts about the Iraqi security forces’ ability to stand alone.
Last week, a string of bombings targeted Shia worshippers in the Baghdad during Friday prayers, killing at least 29 people.