At least 27 people have been killed in a series of attacks targeting the Shi'ite Muslim districts of Baghdad.
Nineteen people were killed and 40 were wounded in an explosion on a bus in Aden square area of Baghdad.
And in another attack near the Khadamiya shrine, a suicide bomber blew himself up after an exchange of fire with security forces, killing two, including a US soldier.
A mortar attack close to the Al-Nida mosque in the northern Baghdad Sunni district of Adhamiya left six people dead.
In other incidents at least 10 more people were wounded.
The attacks came as Iraq's long oppressed Shi'ite majority observed Ashura, marking the 7th century martyrdom of the Prophet Mohammad's grandson.
