At least five people have been killed in a double car bombing at a market in the southern Iraqi city of Diwaniya, officials say.
The cars exploded simultaneously at about 07:30 (04:30 GMT), police said.
The attack in the mainly Shia city comes amid heightened tensions between Iraq's Sunni and Shia communities.
At a Sunni protest in Ramadi, west of Baghdad, the finance minister Rafie al-Issawi announced his resignation from the Shia-led government.
Mr Issawi is the most high profile Sunni member of the government, led by Shia Prime Minister Nouri Maliki.
The arrest of his bodyguards in December last year sparked Sunni anti-government protests that have continued in several cities.
String of attacks
Protesters accuse Mr Maliki of attempting to monopolise power and marginalise the Sunni minority.
Although sectarian violence has decreased in Iraq since the height of the insurgency in 2006 and 2007, bombings and shootings are still common.
There has been a string of bomb attacks across Iraq in recent months.
Sunni insurgents linked to al-Qaeda have been blamed for the rise in violence, although no-one has claimed responsibility for Friday's attack.
Reuters news agency said the target was a sheep market in Diwaniya, about 130km (80 miles) south of Baghdad.
"I came to buy some calves and was checking them when the explosion happened. I threw myself on the ground, then the second explosion happened," Jassim Khalid, a butcher, told the agency.
It comes a day after at least 22 people were killed in a series of bomb attacks in Shia neighbourhoods of the capital, Baghdad.