Two protesters died in Baghdad early Monday after being shot with tear gas canisters in violent confrontations with Iraqi security forces, medical sources told AFP.
Demonstrations over power outages erupted in the capital and several southern cities on Sunday, as temperatures topping 50 degrees Celsius overwhelm electricity generators across the country.
In Baghdad, dozens gathered at the protest hub of Tahrir Square, clashing with police and other security forces stationed there.
An AFP correspondent saw the burnt remains of tent structures in the square on Monday morning.
The deaths were the first since Prime Minister Mustafa al- Kadhimi, who had promised a dialogue with protesters, took office in May.
In a statement overnight, his office acknowledged "unfortunate events" in protest squares, but insisted security forces had been instructed not to use violence unless absolutely necessary.
It said the government would carry out an investigation into Sunday's events to hold those responsible to account.