A series of car bombs in and around Baghdad on Sunday morning killed five people and wounded 22 others, an interior ministry official said.
The attacks came after a spate of violence across Iraq last week killed 116 people, breaking a relative calm that had settled after the formation of a new government a month ago.
In the worst attack, a car bomb targeting a police patrol in the Al-Alam neighbourhood of southwest Baghdad killed two people, including one policemen, and wounded eight others, among them four police, the official said.
Another vehicle packed with explosives was detonated on Abu Nawas street, on the banks of the Tigris river which snakes through the capital, leaving one person dead and six others wounded.
Four other people were wounded, including a policeman, in a separate car bomb attack in the commercial Karrada district in the centre of Baghdad.
And on a main road in the town of Taji, 25 kilometres (15 miles) north of the capital, a bomb-filled vehicle was blown up, killing two people and wounding four others.
While violence has dropped dramatically across Iraq since its peak in 2006 and 2007, attacks remain common, as a series of blasts, which included suicide bombs, last week illustrated.
The attacks, which targeted security force members and Shiite pilgrims ahead of major commemoration ceremonies, killed 116 people and wounded scores more in the cities of Tikrit, Baquba, Baghdad and Karbala over a three-day period.
By contrast, 151 people were killed throughout December.
The apparent spike in violence comes just a month after Prime Minister Nuri al-Maliki formed a new government, ending a protracted political stalemate following elections in March.
He has yet to appoint ministers charged with the interior, defence or national security portfolios, however, and currently holds interim responsibility for the entire Iraqi security apparatus.