Four protesters killed in Baghdad, southern port blocked.

Four protesters shot dead at least in central Baghdad on Thursday, police and medical sources said, as weeks of deadly unrest showed no signs of abating.

Another 35 people were wounded in the clashes near Shuhada Bridge, they said, as mass demonstrations continued for a 13th straight day with thousands thronging central areas of the capital.

In southern Iraq, dozens of protesters burned tires and blocked the entrance to the port of Umm Qasr, preventing trucks from transporting vital food imports, just hours after operations had resumed, port officials said.

The Iraqi government has failed to find a way out of the biggest and most complicated challenge to its rule in years. The unrest has shattered the relative calm that followed the defeat of the Sunni Muslim extremist Islamic State in 2017.

A crackdown by authorities against mostly unarmed protesters has killed more than 250 people since unrest broke out on Oct. 1 over lack of jobs and infrastructure wrecked by decades of conflict, sanctions, and corruption.

Protesters, mostly unemployed youth, blame a political elite that has ruled Iraq since the toppling of dictator Saddam Hussein in a 2003 US-led invasion and demand a complete overhaul of the political system.

The country is beginning to feel the fiscal pinch of weeks of the unrest, which started in Baghdad and quickly spread to southern cities.

The new stoppage of operations at Umm Qasr port in the south is likely to compound financial losses a day after the government said that a week-long halt of operations there had cost more than $6 billion.

Meanwhile, ongoing internet outages imposed by the government to try to stem unrest have hit the private sector, a central bank source said.

The source said private banks in Iraq had recorded losses of some $16 million per day since the internet was first shut down at the beginning of October.

Combined losses by the private banks and mobile phone companies, money transfer services, tourism, and airline booking offices had averaged more than $40 million per day, the source said – almost $1.5 billion for Iraq in just over a month.

Umm Qasr briefly resumed operations early on Thursday after most protesters cleared the area. But several dozen activists, relatives of a demonstrator killed during weeks of violence, then returned to block the main gate, port officials said.

Umm Qasr receives most of the grain, vegetable oils, and sugar that Iraq depends upon.

Oil and security officials said operations resumed on Thursday at the nearby Nassiriya oil refinery, where protesters had stopped fuel tankers entering or leaving the day before.

Oil production and exports have not been significantly affected by the unrest, oil ministry officials say.

But the halting of fuel tankers that transport fuel from the Nassiriya refinery to regional gas stations caused fuel shortages across the southern Iraqi province of Dhi Qar. The refinery had recently been producing around half its capacity, oil officials said.

Internet returned briefly in most parts of Iraq on Thursday but went out again after 1:00 p.m. local time (1000 GMT). Authorities have heavily restricted internet access during the protests.

The government says it is enacting reforms but has offered nothing that is likely to satisfy most protesters.

Stipends for the poor, more job opportunities for graduates and pledges to punish a handful of corrupt officials have come too late for those demanding an overhaul of state institutions, a flawed electoral process and system of governance that has fueled endemic corruption, many Iraqis say.