Blasts at a passport and identity card office in the Iraqi Shiite shrine city of Karbala killed 10 people on Sunday, with Prime Minister Nuri al-Maliki urging unity in the face of "sectarianism".
The series of four explosions in Karbala also wounded around 100 others and caused major damage to nearby vehicles and buildings, leading security forces to cordon off the scene and close all entrances to the city.
Maliki and parliament Speaker Osama al-Nujaifi both quickly condemned the attack, with the premier saying the violence "emphasised the need to unify our response and... stop making remarks that help achieve the targets of criminals and those who are trying to raise sectarianism."
An initial roadside bomb at 9:30 am (0630 GMT) in the centre of the city, 110 kilometres (70 miles) south of the capital, was followed by three more blasts once emergency services arrived, a police officer and a provincial official said.
"The final toll from the bombings in Karbala today is 10 killed and 110 wounded, including children and women," said Alaa Hammudi, head of Karbala province's health department.
Lieutenant General Othman al-Ghanimi, the army commander for forces across five provinces in central Iraq, including Karbala, put the toll at 10 dead and 86 wounded.
He said the four explosions included two roadside bombs, a car bomb and a suicide explosion, but did not say the order in which they happened.
An AFP journalist at the scene reported seeing several bodies covered in blood being taken away by paramedics, and major damage to vehicles and buildings, with some houses completely collapsed.
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Security forces cordoned off the area in the aftermath of the attacks, the journalist said. An interior ministry official said entrances to the city had been closed.
Karbala is a predominantly Shiite city that is home to the mausoleums of Imam Hussein and his half-brother Abbas.
It has frequently been the target of Sunni insurgents in the past, such as on January 20 when a spate of blasts against Shiite pilgrims on the outskirts of Karbala killed 45 people.
More recently, Sunni insurgents in western Anbar province stopped a bus carrying Shiite pilgrims from Karbala to a shrine in Syria earlier this month, and killed 22 male passengers.
In the western city of Ramadi, meanwhile, two roadside bombs killed two people and wounded six others, including two young girls, a police officer and an anti-Al-Qaeda militiaman said.
An initial explosion at the home of tribal chief Mohammed Awwad killed a woman and wounded the girls, the security officials said. The second, which occurred when police arrived, killed a man and wounded four others, including three policemen.
Ramadi is the capital of Anbar, a key Sunni insurgent base in the years after the US-led invasion of 2003, but since 2006 local tribes have sided with the American military and day-to-day violence has dropped dramatically.
In the north Baghdad neighbourhood of Hurriyah, meanwhile, the driver of a senior official in Iraq's human rights ministry was killed by gunmen using silenced pistols, an interior ministry official said.
Violence is down across Iraq from its peak in 2006 and 2007, but attacks remain common. A total of 239 people were killed in violence in Iraq in August, according to official figures.