The morning attack caused a fire at the popular Isterbadi market in the predominantly Shia northern suburb of al-Kadhimiya, but the blaze was extinguished, police Captain Muhammad al-Waili said.
Elsewhere, a bomb left in a plastic bag struck an outdoor market where secondhand goods are sold at about 10.15am in central Baghdad, killing two civilians and wounding 24, police Lieutenant Ahmad Muhammad Ali said. Some of the wounded were in a critical condition, he said.
A roadside bomb also missed a police patrol in the Karrada neighbourhood in central Baghdad, killing one civilian and wounding two, police Colonel Abbas Muhammad said.
The series of explosions came a day after a suspected shoe bomber targeting a Shia imam who criticized Abu Musab al-Zarqawi blew himself inside one of Baghdad's most prominent mosques during Friday prayers, killing 13 people.
A soldier in the US-led coalition also was killed on Friday and two others were missing after an attack on a checkpoint near the town of al-Yusufiyah, about 12 miles southwest of Baghdad, the US military said.
Iraqi authorities carried out a security operation on Wednesday, with 75,000 troops on the streets of Baghdad, to try to curb the violence that has devastated the capital of six million people.