Iraqi security forces have shot dead 14 protesters in the southern city of Nassiriya, medical sources say, and authorities have imposed a curfew in Najaf after demonstrators burned an Iranian consulate.
Authorities set up joint military-civilian "crisis cells" to try to stem unrest.
The torching of the consulate in Najaf, the southern holy city, escalated violence in Iraq after weeks of mass demonstrations that aim to bring down a government seen as corrupt and backed by Tehran.
The inability of Iraq's government and political class to deal with the unrest and answer protesters' demands has fuelled public anger.
Prime Minister Adel Abdul Mahdi has promised electoral and anti-corruption reform but barely begun delivering while security forces have shot dead hundreds of mostly peaceful demonstrators in the streets of Baghdad and southern cities.
The protests, which began in Baghdad on October 1 and have spread through southern cities, are the most complex challenge facing the Shi'ite-dominated ruling class that has controlled state institutions and patronage networks since the 2003 US-led invasion that toppled long-time Sunni ruler Saddam Hussein.
Young, mostly Shi'ite protesters say politicians are corrupt, beholden to foreign powers - especially Iran - and they blame them for a failure to recover from years of conflict despite relative calm since the defeat of Islamic State in 2017.
Security forces opened fire on protesters who had gathered on a bridge in Nassiriya before dawn, medical sources said. Fourteen were killed and dozens were wounded, they said.
A curfew was imposed in Najaf after protesters stormed and set fire to the Iranian consulate late on Wednesday. Businesses and government offices remained closed in the city, state media reported.
It was the strongest expression yet of the anti-Iranian sentiment of Iraqi demonstrators.
The violence has killed more than 350 people, according to police and medics.
Reuters