Five IS commanders captured crossing into Iraq from Syria
US intelligence also assisted in the cross-border sting, which had been in the works for three months tracking the group of leaders through Turkey and Syria, two Iraqi officials told The New York Times.
The five commanders, described as "some of the most wanted" leaders of the extremist group, were named as Saddam al-Jammel, Mohammed al-Qadeer, Ismail al-Eithawi, Omar al-Karbouli and Essam al-Zawbai - four are said to be Iraqi and one of Syrian nationality. They were shown on TV in yellow prison uniforms.
Read more: The Iraq Report: Iraq attempts to move on after Islamic State defeat
Iraqi Prime Minister Haider al-Abadi vowed last month to "take all necessary measures" against IS militants in Syria. Iraq has been carrying out airstrikes on militant positions in neighbouring Syria since last year.
Despite Abadi's declaration of "victory over IS" in December, the group have shown a resurgence, carrying out deadly attacks across Iraq in the run-up to parliamentary elections this month.
Meanwhile, the leader of the Islamic State group Abu Bakr al-Baghdadi is said to be hiding in eastern Syria, moving around with only a small group of followersv - including one of his sons - according to an Iraqi intelligence official.
The senior Iraqi official said Baghdadi was in the Hajin, Shaddadi, Suwar and Markadah areas and "travels accompanied by four or five people, including his son and son-in-law".
"His movements are discreet and he never travels in a convoy," the official said on condition of anonymity.
Originally from Iraq, Baghdadi has been dubbed the "most wanted man on the planet" and the United States is offering a $25 million reward for his capture.
The intelligence official added that the capture of the five commanders signalled a that Baghdadi's time may soon be up, adding that the cross-border raid occured on 24 March.
The five men had featured in IS execution videos filmed while the group ruled over vast swathes of Iraq, the official said.
One of those detained, former Syrian anti-government fighter Saddam al-Jamal, allegedly confessed to Iraqi forces that he had supplied IS with arms stolen from the Syrian army.
The official said 39 IS fighters had been killed in cross-border air raids by Iraqi forces in Syria over the past few weeks and that the group had seen a "sharp decrease" in numbers.
Iraq's interior ministry said in February that Baghdadi was being treated at a field hospital for wounds sustained in an earlier airstrike.
In mid-2017, Russia said it had probably killed Baghdadi in a late May air raid near Raqqa in Syria, but later said it was still trying to verify his fate.
In September, an American military chief said the jihadist chief was still alive and probably hiding in eastern Syria's Euphrates Valley.
Agencies contributed to this report.