A series of attacks across Iraq on Friday killed 17 people, including four Shiite militiamen and a Sunni tribal chief, while a mass grave in the north was found to contain the bodies of 15 Shiite truck drivers killed by Sunni militants.
Police officials said the deadliest attack happened when a car bomb went off on a commercial street in Baghdad's mainly Shiite Zafaraniyah district, killing seven people and wounding 15 others. Several shops were damaged.
South of Baghdad, a roadside bomb targeted a Shiite militia convoy, killing four fighters and wounding seven in the area of Iskandariyah.
Shiite militiamen have joined with Iraq's armed forces in their battle against the extremist Islamic State group, which has seized large swaths of land as well as cities and towns in the country's north and west.
Another bomb went off near an outdoor market in Baghdad's Shiite district of Obeidi, killing three shoppers and wounding 12, police said.
In northern Iraq, residents said Islamic State fighters killed Maiser al-Waqaa, a Sunni tribal chief, along with two brothers in the village of al-Houd, just south of Mosul.
They said al-Waqaa ran in parliamentary elections earlier this year but failed to win a seat.
Sunni militants captured Mosul, Iraq's second largest city, and overran much of northern Iraq in June. The Islamic State group has carved out a self-styled caliphate straddling the Iraqi-Syrian border.
Medical officials confirmed the casualties from all attacks. All officials spoke of condition of anonymity because they are not authorized to speak to the media.
Elsewhere in the north, a mass grave containing the remains of the Shiite truck drivers was found in the Suleiman Beg area. Families of the drivers said they were abducted about three months ago by Sunni militants, who captured the town during their June offensive.
Abu Ahmed, the father of one of the victims, said one of the captors contacted him with his son's mobile phone and asked where the family was from. When he replied that they were from Karbala, a Shiite holy city in central Iraq, the man hung up. Abu Ahmed never heard from his son again.
The grieving father asked not to be identified by his full name for fear of retribution.
The grave was found after Iraqi security forces and Shiite militiamen drove out the Islamic State fighters earlier this week. The bodies had each been shot in the head. The excavation was carried out by volunteers and nurses based on information provided by local residents and families of the victims.
Suleiman Beg is about 150 kilometers (95 miles) north of Baghdad.