Iraqis on Monday protested for the third consecutive day against power cuts, water shortages and poor water quality in the south as temperatures soared above 50°C across the country.
The blackout was caused by the failure of a power line and a fire at a power plant, which affected southern provinces and the oil-rich city of Basra. Groups of young Iraqis set fire to tyres to block roads as they demanded the return of electricity to the city.
Power was reportedly restored in some districts of the port city by Monday afternoon.
Basra Governor Asaad Al Eidani said the third power cut in a short space of time was "due to a fire at Khor Al Zubayr station".
Khor Al Zubayr produces up to 500 megawatts of Basra's 3,000MW electricity demand.
Mr Al Eidani said the fire was put out and the damage repaired.
The country's Electricity Ministry last week announced a state of "general alert" in the face of rising temperatures, as it predicted an increase in demand for services.
Basra was not the only governorate to be affected, but it has the highest concentration of residents and some of the worst access to services in the south of the country.
In Najaf, the local authorities said on Monday that electricity shortages had caused problems pumping water for domestic supply, a long-term issue in many Iraqi cities where water and sewage treatment systems rely on power from the national grid.
At the weekend, protesters tried to storm one of Basra's largest power plants after the blackout and similar protests were reported near power stations in nearby Maysan province.
The ministry said the power cuts were due to "unprecedented high temperatures".
Blackouts in Iraq often happen at the height of summer when demand increases by up to 10 gigawatts.
Iraq produces about 23 gigawatts of power, but demand in the summer is thought to exceed 30 gigawatts.
The harsh environment affects equipment running at maximum capacity, which can also contribute to power cuts.
Defects in the transmission and distribution network can also contribute to blackouts, while less power reaches homes owing to Iraq's ageing electricity grid.
Anger over power cuts has previously resulted in mass demonstrations that at times turned deadly as protesters clashed with security forces.
For years, Basra has been the site of violent protests.
In late 2019, more than 500 people were killed during months of anti-government demonstrations that erupted under former prime minister Adel Abdul Mahdi, affecting Baghdad and southern towns including Basra.
The previous year, protests erupted in Basra after 100,000 people fell ill after heavily polluted saline water was distributed for domestic use.
Protesters were mostly young Iraqis who were unarmed.
Since the US-led invasion in 2003, the country has faced regular summer power cuts, a situation exacerbated by years of conflict that followed the invasion.
On Monday, Shiite cleric and political leader Moqtada Al Sadr called on Iraqi protesters to unite to support reform and improve services. This call included secular demonstrators who suffered in the 2019 crackdowns — known as the Tishreen, or "October" movement after the month they took to the streets — to his own devout followers.
Both the Sadrists and Tishreen protesters had been aligned before, but the cleric's loyalists later attacked protest camps in Najaf in February 2020, killing seven people.
The compounding, linked crises Iraq faces in summer show no sign of abating amid a 10-month political standoff that has delayed the formation of a new national government.
Iraq is ranked as one of the world’s five most vulnerable nations to the effects of climate change.
In recent months, a series of sandstorms swept across the country and thousands of people were taken to hospital with respiratory problems.