Three separate blasts killed at least 16 people on Saturday, adding to questions about the ability of Iraq's security forces to control the violence that has swirled after a spate of deadly bombings this month.
The attacks underscored the challenges of providing security, especially in remote areas and in the north, where two of the bombings struck and where ethnic tensions have mounted.
Insurgents drove a truck filled with explosives to a police garrison on the main street of the village of Hamad, south of the restive city of Mosul. The blast was so powerful that it killed not only five members of the security forces at the station, but also at least five residents in neighboring houses, according to witnesses. Fourteen people were wounded, officials said.
Hamad, a mainly Sunni village, is surrounded by desert, making it somewhat more vulnerable as Iraq's security forces focus their efforts on cities.
The other major attack on Saturday occurred in Sinjar, a town west of Mosul and near the border with Syria; the area is home to the Yazidis, Kurdish-speaking followers of a pre-Islamic faith with roots in Zoroastrianism. There, a bomb in a truck parked at a local market killed four people and wounded 23.
Later Saturday night, two more people were killed and 14 wounded when a suicide bomber on a motorcycle drove into a market in eastern Baghdad.
Sinjar has been disproportionately hit by attacks. Earlier this month, two bombers wearing suicide vests attacked a popular cafe crowded with young people there, killing 21.
Separately, thousands of Iraqis turned out in the holy city of Najaf for the burial of the Shiite leader Abdul-Aziz al-Hakim, who died Wednesday of lung cancer.
Amid high security, his body was driven to a cemetery to be buried next to an older brother, Ayatollah Muhammad Bakr al-Hakim, a revered Shiite figure who was killed in a bombing a few months after the U.S.-led invasion in 2003.