In two other Baghdad areas, a doctor was killed when a bomb attached to his car exploded and a police officer was shot dead while driving his car, police said.
In Abu Ghraib, just west of Baghdad, one worshipper was killed and six others were wounded when a bomb went off near a Sunni mosque, police said.
To the north of the Iraqi capital, a bomb targeted a patrol of pro-government anti-al-Qaida Sunni militiamen in the town of Tarmiyah, killing three and wounding two, police said. Al-Qaida sees the militia, known as an Awakening Council, as traitors since it was set up by U.S. forces during the height of Iraq's insurgency. Tarmiyah is located about 50 kilometers (30 miles) from Baghdad.
Militants attacked a police station and an army patrol near the northern city of Mosul, killing two policemen and two soldiers and wounding seven troops in those attacks. Mosul is located about 360 kilometers (225 miles) northwest of Baghdad.
Medical officials confirmed the causality figures. All officials spoke on condition of anonymity because they were not authorized to talk to journalists.
The explosions came a day after a series of attacks killed at least 50 people on Thursday. And on Wednesday, coordinated explosions hit mainly Shiite commercial areas in Baghdad and outside the capital, killing at least 35 people.
Bombings and militant attacks have spiked since April, when security forces carried out a bloody raid on a Sunni protest camp in the country's north, pushing violence to the highest levels in years and killing more than 5,500 people, according to the United Nations.
Friday's attacks bring the death toll across the country this month to 317, according to an Associated Press count.
