BEIRUT — One of ISIS leader Abu Bakr al-Baghdadi's wives and children have been arrested in Lebanon, the country's defense ministry confirmed to NBC News. Col. Anis Khoury, a spokesman for the ministry, declined to offer further details and said the army is leading the investigation.

News of the arrest was initially reported by Reuters, which said the wife and a child were detained several days ago as they crossed from Syria. Lebanon's leading Al Safir newspaper said the arrest was undertaken "in coordination with foreign intelligence services" and that Baghdadi's wife was travelling under a false identity.

Little is known about Baghdadi, who is rarely seen or heard from. An audio-tape released by ISIS last month and purportedly from the militant chief called for "volcanoes of jihad" to erupt the world over.

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A biography released by ISIS supporters in July said Baghdadi is married, but it is unclear who his wife is — or if he has more than one.

Born in Iraq's city of Samarra, Baghdadi has been portrayed in jihadist propaganda as an imam from a religious family descended from noble tribes, and a scholar and a poet with a Ph.D. from Baghdad's Islamic University, possibly in Arabic. He ended up at the U.S. detention facility Camp Bucca in 2004 and after his release rose through the ranks of the Islamic State of Iraq — the terror successor to Abu Musab al-Zarqawi's al Qaeda in Iraq.

When the organization's leaders were killed in 2010, Baghdadi stepped into the void. Baghdadi — which is not his birth name — uses a host of aliases and is said to wear a bandana around his face to conceal his identity from everyone except a very tight inner circle that is thought to be comprised only of Iraqis.

When fighting in Syria intensified in the summer of 2011, Baghdadi saw an opportunity and opened a branch there and changed the name of his group to ISIS. His forces have since seized territory in Syria and Iraq which is home to several million people.

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— Mustafa Kassem, Cassandra Vinograd and Charlene Gubash