Updated

Gunmen killed five people, including two soldiers, in Iraq on Thursday, officials said, the latest in a spike in violence that the government has so far failed to stem.

Security forces have in recent weeks carried out some of their biggest operations since the 2011 withdrawal of US forces, but analysts and diplomats have said authorities have not addressed the root causes of the violence.

In the northern province of Nineveh, gunmen killed four people, including two soldiers, and wounded another in two separate attacks, one of them targeting a checkpoint, an army officer and a doctor said.

In the northern city of Kirkuk, gunmen kidnapped and executed a lawyer, while a car bomb in a government car park wounded four people, police and a doctor said.

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.

Attacks have killed more than 3,550 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 Prime Minister Nuri al-Maliki has vowed to press on with the security force operations, insisting they are producing results.