The US-led coalition unleashed airstrikes near the Iraqi city of Mosul have targeted top jihadist militants but the fate of the Islamic State group's enigmatic leader remained unclear.
Claims swirled that hardline IS chief Abu Bakr al-Baghdadi had been killed in the attacks late Friday, but US officials could not confirm if he had even been present.
The news came after US President Barack Obama unveiled plans to send up to 1,500 more US troops to Iraq to help battle the militants who have seized a large swathe of territory.
In fresh violence, some 33 people were killed in a wave of car bombings against Shi'ite areas in the capital Baghdad, highlighting again the security challenge facing Iraqis even within government-controlled zones.
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US Central Command confirmed that coalition aircraft conducted a "series of airstrikes" against "a gathering of ISIL leaders near Mosul."
A convoy of 10 armoured vehicles from the group also known as ISIL was destroyed.
"We cannot confirm if ISIL leader Abu Bakr al-Baghdadi was among those present," CENTCOM spokesman Patrick Ryder said in his statement.
A strike against Baghdadi, who has proclaimed himself the "caliph" of a state straddling Iraq and Syria, would be a major coup for the US-led coalition.
Washington has offered a $US10 million ($A10.82 million) reward for his capture, and some analysts say he is increasingly seen as more powerful than Al-Qaeda chief Ayman al-Zawahiri.
In a video posted online in July, purportedly the first known footage of Baghdadi, he ordered all Muslims to obey him during a Ramadan sermon in Mosul.
Al-Arabiya TV reported Baghdadi had been wounded, while a local Iraqi channel said one of his aides was killed.
Iraqi leaders said the new US military trainers who will aid its fight against jihadists are welcome, but come "late."
Ryder added the US-led strikes were a further sign of "the pressure we continue to place on the ISIL terrorist network."
The aim was to squeeze the group and ensure it had "increasingly limited freedom to manoeuvre, communicate and command."
The new troops will roughly double the number of American soldiers already in the country and marks a deepening US commitment in the open-ended war.
"This step is a little late, but we welcome it," a statement from Iraqi Prime Minister Haidar al-Abadi's office said.
The government had requested that members of the international coalition help train and arm its forces, the statement said.
Multiple Iraqi army divisions collapsed in the early days of the jihadist northern offensive, leaving major units that need to be reconstituted.
