In Baghdad, crowds of anti-government demonstrators thronged Tahrir Square, the epicentre of their movement.
Relentless anti-government street protests have been witnessed in Iraq since early October.
After nightfall, armed men on pick-up trucks attacked a large building where protesters had been camped out for weeks near the capital's Al-Sinek bridge.
There were over a dozen knife attacks by the late afternoon when protesters aligned with political parties and Iran-backed militias withdrew from Tahrir, three demonstrators and a witness said.
The Kut criminal court sentenced the police major to be hanged and jailed a police lieutenant colonel for seven years for their roles in the deaths of seven protesters on November 2.
The grassroots movement is the largest Iraq has seen in decades but also the deadliest, with nearly 400 people dead and more than 15,000 wounded.
On Wednesday, the situation escalated in southern Iraq, prompting the authorities to declare curfew in the Najaf province, where the protesters set the Iranian consulate building on fire.
Protesters blocked access to oil fields and companies around the city, torching as well its Shiite endowment centre, a government body that manages religious sites.
The leaderless, economically driven protests are targeting Iraq's entire political class and calling for the overhaul of the sectarian system established after the 2003 U.S.-led invasion.
More than 250 people have lost their lives since anti-government rallies broke out in Iraq on October 1, but officials have stopped providing casualty numbers.
Karbala, along with Baghdad and cities across southern Iraq, has been gripped by a wave of anti-government protests which have often turned violent, with security forces opening fire.
Around 70 per cent of the deaths were caused by bullet wounds 'to the head or chest', according to the findings published, as Iraq braces for fresh protests on Friday.
Since October 1, according to official figures, more than 100 people have been killed, mostly protesters, and more than 6,000 others wounded.
In a televised address, President Barham Saleh said those who attacked protesters and security forces during mass rallies that have spiralled into violence were 'the enemies of the people'.
More than 100 people have been killed and several thousand wounded in demonstrations increasingly spiralling into violence.