Car bombs targeting Shia Muslims in the Iraqi capital a day before major Ashoura religious commemorations, have killed at least 28 people, security and medical officials said.

The first of Sunday's blasts struck near a tent from which Shia Muslims were distributing tea and water in the mixed neighbourhood of Saidiyah in southwest Baghdad. Twenty others were wounded in the attack.

Another car bomb later exploded near another tent used by Shia pilgrims preparing for Ashoura in central Baghdad's Sadoun commercial street, killing at least five people and wounding 13 others, police told Al Jazeera.

And at night, 13 people were killed as a parked car bomb blew up in Sadr City, in eastern Baghdad. That attack also targeted a Shia hospitality tent and injured 34 people, police told Al Jazeera. 

Hundreds of thousands of Shia Muslims flock to the Iraqi shrine city of Karbala for Ashoura, which marks the death of Imam Hussein, one of the most revered figures for Shia Muslims.

Pilgrims have been targeted during Ashoura before, but this year's commemorations, which peak on Tuesday, face even greater danger with the Islamic State of Iraq and Levant in control of large areas of the country.

ISIL, like al-Qaeda, consider the Shia to be heretics and frequently targets them with bombings. 

Keeping the pilgrimage safe from violence is a major test for the country's new government headed by Prime Minister Haider al-Abbadi, as well as Iraq's security forces who have struggled to push back ISIL. 

Source: Al Jazeera and agencies