Kurdish security forces opened fire on a crowd of protesters surrounding the headquarters of the party affiliated with the Kurdish president.
Hundreds of demonstrators gathered in the northern city of Sulaimaniyah, 160 miles (260 kilometers) northeast of Baghdad Thursday, demanding political reforms.
They then moved to the headquarters of Kurdish President Massoud Barzani's political party, where some protesters threw stones at the building.
Kurdish security guards on the roof then opened fire on the demonstrators.
An Associated Press reporter on the scene saw at least five people who were injured in the incident.
Rallies against corruption, poor basic services and high unemployment in several cities across Iraq have also left more than 100 people wounded.
The rare demonstrations in the autonomous Kurdish region were the deadliest since the 2003 U.S.-led invasion that ousted Saddam Hussein.
Iraqi and Kurdish leaders have pledged to bring the perpetrators of the violence to justice. They have also attempted to head off the protests by slashing the salaries of ministers and MPs and diverting cash earmarked for the purchase of fighter jets to buy food for the needy.
Opposition’s offices looted
A Kurdish regional opposition's offices were targeted by looters, officials said Friday.
On Friday, officials said looters had targeted seven offices belonging to the Goran opposition party in the northern Kurdish provinces of Arbil and Dohuk in response to violent protests a day ealier in the region's second city of Sulaimaniyah against the main ruling Kurdistan Democratic Party (KDP).
Goran has denied any involvement in Thursday's demonstration, which left two dead, men aged 18 and 25, and 54 wounded, according to provincial health chief Raykot Hama Rashid, when security forces fired into the air to disperse crowds.
By mid-day Friday, an AFP journalist and Arbil province's governor said Kurdish security forces had evicted the looters from the Goran offices and party officials, who accused KDP loyalists of involvement in the attacks, said they would return to the sites once the situation had calmed.
For decades, the KDP and the Patriotic Union of Kurdistan of Iraq's President Jalal Talabani have lorded over the region, comprised of three provinces, with Goran only emerging in 2009 as a credible opposition.
Thursday's deaths followed violent demonstrations a day earlier in the southern city of Kut where one person was killed and 47 others wounded, with the latest violence prompting New York-based watchdog Human Rights Watch to call for "an independent and transparent investigation".
Meanwhile, protesters blocking a bridge in the southern Iraqi city of Basra are calling for the provincial governor to resign, as the drumbeat of demonstrations railing against the government continues across Iraq.
About 1,000 people rallied Friday in Basra, Iraq's second-largest city, 340 miles (550 kilometers) southeast of Baghdad, to demand better services from the government, jobs and improved pensions.
They shouted slogans warning that today's demonstration was peaceful but ones in the future might not be.
"I have filed my papers with the provincial council but have gotten no job until now," said Hussein Abdel, an unemployed 25-year-old. "There is corruption in Basra -- they have to start taking care of this city and must stop making fake promises."
About 600 people gathered in front of the Basra provincial headquarters, facing off against police protecting the building. With the exception of some pushing and shoving between protesters and police, witnesses said the protest was largely peaceful.
A day earlier in the city of Kut, about 2,000 stone-throwing demonstrators attacked local government offices, setting fire to some buildings, including the governor's house. Kut is 100 miles (160 kilometers) southeast of Baghdad.
Witnesses said Iraqi police and soldiers shot at demonstrators who pelted the offices with stones and commandeered military vehicles. The spokeswoman for Wasit province, Sondos al-Dahabi, said Thursday that three demonstrators were shot and killed. Al-Dahabi put the number of the wounded at 30, including 15 policemen.
The top health official for the province, Diaa al-Aboudi, said he was only aware of one fatality, an Iraqi soldier. Fifty-five people were injured, he said. Some were shot while others were hit by stones thrown by demonstrators or burned in the melee.
Prime Minister Nuri al-Maliki said Thursday that peaceful protests were the right of all Iraqis, but warned that those inciting violence would be brought to justice.
"I welcome those who demonstrate peacefully for their legitimate rights, but I am not in favor of those who exploit those claims to incite riots," he told reporters in Baghdad.
"The perpetrators will be brought to court and they will be punished."