This break was the arrest in May of one of al-Baghdad's brothers-in-law, Mohammed Ali Sajet al-Zubaaei, who joined ISIS in 2015 and had become one of the leader's trusted guides.
It was a culmination of Iraq's tactics to follow al-Baghdadi by looking for those closest to him, said Director General Saad al Allaq, head of Iraq's military intelligence directorate.
"We observed the movements of al-Baghdadi indirectly through his family, al Allaq said in a rare interview." By doing so, it gives us a kind of secret and we gave al-Baghdadi the impression that we did not monitor his movements. "
Al-Zubaaei had helped al-Baghdadi avoid the authorities when he traveled. After he himself was captured by Iraqis on the outskirts of Baghdad in May 201
Al-Zubaaei also suggested that the ISIS chief could be in Idlib, Syria, the agents said.
Iraqi security forces could later infiltrate an al-Baghdadi smuggling network in Syria, which helped track him, they said
News that al-Baghdadi was in Idlib seemed strange to many analysts, CNN's Clarissa Ward reported last month. Idlib is under the control of Hayat Tahrir a Sham, a rebel group with ties to al Qaeda. While militant jihadist groups have many common ideologies, ISIS and al Qaeda and its affiliates have been locked in bitter fighting in Syria for several years. It seems to be an unlikely hiding place for Baghdadi, especially in a village just 3 miles from the Turkish border.
Al Allaq said that much of the ISIS leadership had moved to northern Syria to be closer to its sources of funding. He added that ongoing military operations around the Euphrates River in the Iraq-Syria border area had uncomfortable al-Baghdadi.
"He traveled west to be far from military operations and combat zones," he said.
Operation Falcon Eye
Iraq had chased the elusive ISIS leader since he proclaimed the so-called Caliphate from the Grand Mosque in Mosul in July 2014.
Spies were sent to the city and at least one when The Iraqis sealed an area and thought they could trap him. At that time, he changed his place more than ten times a day, al-Allaq said.
The details of the mission with the code name Operation Falcon Eye were gathered in a presentation shown to CNN by Iraqi military intelligence officials.
They said that al-Baghdadi was in Iraq through the height of the ISIS movement before Iraqi military operations in and around Mosul began to expel the rebels.
Al-Baghdadi fled through ISIS-controlled territory into Syria in August 2017. Iraqi agents continued to track him as he moved north, following the Euphrates road toward Deir Ezzor, where he was in February 2018, officials said
An important role was played during this time by the father of Al-Baghdadi's third wife, who became known as the "ghost of the desert" for his ability to move ISIS groups undiscovered between Mosul in Iraq and Raqqa in Syria, CNN was told.
In February 2018, Iraq says it received another breakthrough with the arrest of Mohammed al-Dulaimi, known as Abu Ibrahim. He was the son of a former deputy to al-Baghdadi who was one of his most important couriers for ISIS coded messages at that time. This arrest generated more information about al-Baghdadi's guide, al-Zubaaei, and was an important step that led to his capture, al Allaq said.
Al-Baghdadi left his hiding place in Deir Ezzor after al-Dulaimi's arrest, officials said. Iraq shared its information with US-led coalition forces and Syrian democratic forces in renewed pressure to track down the ISIS chief.
Iraq's intelligence chiefs said al-Baghdadi then continued to move in the Syrian desert between Palmyra and Homs until at least March this year, before heading north where he was killed last month and killed himself.