ISIS chief Abu Bakr al-Baghdadi is believed to have been killed in a stategic military operation carried out by US in Syria's Idlib region.
According to Reuters, an US official on condition of anonymity, confirmed that the raid at Idib indeed took place but was vague about it's outcome.
However other media quoting multiple government sources said, Baghdadi is dead and is thought to have killed himself with a suicide vest as US special operations forces attacked.
There were several claims of his death in recent years though this time, though reports this time insist it is real.
US president Donald Trump earlier tweeted "Something very big has just happened". Trump is expected to make a major statement at 13:00 GMT today.
Al-Baghdadi led ISIS for the last five years. However his so-called caliphate shrank rapidly in recent years with many supporters who joined the cause either imprisoned or jailed.
The latest strike came amid concerns that a recent US pullback from northeastern Syria could infuse new strength into the group, which had given up vast stretches in territory it once controlled.
