Iraqi security forces fired tear gas and live rounds into the air to disperse protesters in central Baghdad on Wednesday as the biggest wave of anti-government demonstrations in decades spread out across the capital.
Reuters correspondents said the shootings took place on or near three of Baghdad's main bridges - Ahrar, Shuhada, and Bab al-Muatham - which have become focal points of the protests.
There appeared to be no deaths. At least 27 people sustained tear gas-related injuries, medical and security sources said.
Protesters had blocked the Shuhada Bridge over the River Tigris since Tuesday afternoon as part of efforts to bring the country to a standstill, with thousands joining anti-government demonstrations in the capital and southern provinces.
They had tried to take Ahrar Bridge on Monday when security forces opened fire, killing at least five.
"More youth started gathering so they kept firing tear gas and live bullets. Maybe four were injured. We didn't do anything but they came and arrested everyone. The youth are peaceful from the start of the sit-in," Qusay Mahdi, a protester on Shuhada Bridge, said on Wednesday.
Security forces were also arresting protesters en masse. A Reuters correspondent saw police pull over a tuk-tuk in the vicinity of one of the bridges and beat the driver before arresting him.
Clashes over two other bridges near the central Tahrir Square where thousands had been gathering for weeks had been taking place regularly, bringing the total of blocked bridges to five.
More than 260 Iraqis have been killed in demonstrations since the start of October against a political class they see as corrupt and beholden to foreign interests. In the 24 hours to late Tuesday, security forces shot dead at least 13 protesters.
Four more people died on Wednesday from injuries sustained at earlier protests over the past week, medical sources said.
Iraqis have been congregating in Tahrir Square for weeks, demanding an overhaul of the political system in the biggest wave of mass protests since the fall of Saddam Hussein in 2003. Thousands have also been gathering in the impoverished southern Shi'ite heartland.
Since defeating Islamic State in 2017, Iraq has enjoyed two years of comparative stability. But despite its oil wealth, many people live in poverty with limited access to clean water, electricity, healthcare or education.
The root cause of grievances is the sectarian power-sharing system of governance introduced in Iraq after the U.S.-led invasion in 2003.
Many see political elites as subservient to one or another of Baghdad's main allies, the United States and Iran, who use Iraq as a proxy in a struggle for regional influence.
Protesters are now escalating their tactics, saying civil disobedience is their only recourse and calling for strikes as the government of Prime Minister Adel Abdul Mahdi, in office for a year, has found no response to the protests.
Protesters on Wednesday blocked the entrance to the Nassiriya oil refinery, security and oil sources said. They stopped tankers that transport fuel to gas stations from entering the refinery, causing fuel shortages.
Security forces forcibly dispersed a sit-in there overnight in oil-producing Basra but no deaths were reported, security sources said. Protesters had camped out in front the provincial government building.
Thousands have been blocking all roads leading to Iraq's main Gulf port Umm Qasr, near Basra.
Operations at the port, which receives most of Iraq's imports of grain, vegetable oils and sugar, have been at a complete standstill for a week.
The Umm Qasr blockade has cost the country more than $6 billion so far, a spokesman for the prime minister said.
There were clashes there overnight as the families of protesters killed in previous attempts to disperse the sit-in threw rocks at security forces stationed near Basra port. No deaths occurred, security sources said
In a televised address on Tuesday, Abdul Mahdi said the protests were having an economic impact the country could not afford, and he asked demonstrators to refrain from further damaging public and private property.
Security sources said on Wednesday that arrest warrants for protest organisers arrived from Baghdad to all provinces on Tuesday. Dozens have already been arrested in Basra and Nassiriya, they said.
The government's blocking of the internet across much of Iraq has an estimated economic impact to national GDP of over $1 billion in October, said internet outage observatory NetBlocks.
Internet remained blocked across much of Iraq on Wednesday, having been completely shutdown late on Monday and briefly restored for less than four hours on Tuesday morning.
The US Embassy in Baghdad on Wednesday condemned the deadly violence against unarmed demonstrators, and urged Iraq's leaders to engage urgently with the thousands who have been protesting.
Protesters had blocked the Shuhada Bridge over the River Tigris since Tuesday afternoon as part of efforts to bring the country to a standstill.