Violence in Iraq killed seven people on Friday, the latest in worsening unrest that has hit the country despite weeks of wide-ranging operations targeting militants.

Prime Minister Nuri al-Maliki has vowed to press on with the anti-insurgent campaign, which is among the biggest since US forces withdrew in December 2011, but analysts and diplomats say authorities have failed to tackle the root causes of the violence.

Friday's violence struck across the country -- in Baghdad and to its north and south -- with gun and bomb attacks hitting both Shiite and Sunni areas.

In the deadliest incident, gunmen burst into a house in a mostly Shiite town north of Baghdad and killed three people.

Violence in Hilla, south of the capital but also predominantly Shiite, left two dead.

Five separate shootings and explosions in the capital Baghdad and Mosul, a mostly Sunni Arab city in north Iraq, killed two people and wounded 10 others.

Violence has surged in Iraq this year to levels not seen since 2008, when the country was emerging from a brutal Sunni-Shiite sectarian conflict that claimed tens of thousands of lives.

Attacks have killed more than 3,580 people since the beginning of 2013, according to figures compiled by AFP.

Analysts and diplomats link the increased bloodshed to anger among Iraq's Sunni Arab minority over their alleged ill-treatment at the hands of the Shiite-led government.

But the prime minister has vowed to press on with the security force operations, insisting they are producing results, pointing to the arrest of hundreds of alleged militants and the killing of dozens of others.