From 'caliph' to fugitive - IS leader Baghdadi's new life on the run

FILE PHOTO: A man purported to be the reclusive leader of the militant Islamic State Abu Bakr al-Baghdadi making what would have been his first public appearance, at a mosque in the centre of Iraq's second city, Mosul, according to a video recording posted on the Internet on July 5, 2014, in this still image taken from video. REUTERS/Social Media Website via Reuters TV/File Photo

BAGHDAD/ERBIL, Iraq (Reuters) - Islamic State leader Abu Bakr al-Baghdadi is on the brink of losing the two main centres of his 'caliphate' but even though he is on the run, it may take years to capture or kill him, officials and experts said.

Islamic State fighters are close to defeat in the twin capitals of the group's territory, Mosul in Iraq and Raqqa in Syria, and officials say Baghdadi is steering clear of both, hiding in thousands of square miles of desert between the two.