The man, identified by police and hospital officials as Talal Ali Abbas, ignited himself in a central square in Mosul where protesters have been rallying for weeks. They say other protesters quickly put the blaze out by smothering the flames with their coats.
Abbas, 26, suffered burns on about 20 percent of his body, particularly on his hands, according to a doctor at a hospital where he is being treated. His injuries did not appear to be life-threatening. Police said he has been detained on several occasions.
The officials spoke on condition of anonymity because they were not allowed to release the information to reporters.
Iraq's minority Sunnis began protesting last month in Iraq's western Anbar province following the arrest of bodyguards assigned to Sunni Finance Minister Rafia al-Issawi. The rallies have since spread to other parts of the country with sizable Sunni communities, including Mosul, about 360 kilometers (225 miles) northwest of Baghdad.
The protesters are demanding concessions and reforms to policies they say unfairly target their sect, including the release of detainees and changes to tough counterterrorism laws. Many Sunnis feel they have been treated unfairly since the ouster of Saddam Hussein, a Sunni, in the 2003 U.
Prime Minister Nouri al-Maliki's administration recently released hundreds of inmates in an effort to calm the demonstrations. He has appointed a top deputy to oversee a committee to consider protesters' demands.
Those moves have done little to quiet Sunni anger. The demonstrators are increasingly tying their rallies to those that swept other parts of the region during the Arab Spring, with many calling for the downfall of al-Maliki's Shiite-led unity government.
Protest organizer Ghanim al-Abid urged other protesters not to emulate the man's action and said demonstrators would prevent anyone else from trying to copy him.
"We reject this kind of action. We do not want to see people burning themselves. This is not a source of pride in our society," he said.
Tunisian vendor Mohamed Bouazizi's setting himself on fire in protest over abuses under the regime of longtime President Zine El Abidine Ben Ali in December 2010 is widely seen as the spark that set off the wave of change that has reshaped the Arab world.
Associated Press writer Sameer N. Yacoub contributed.
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