How 'bad-ass librarians' saved Islamic treasures in Timbuktu

For centuries the desert city of Timbuktu was the intellectual centre of the Islamic World and a home to thousands of precious manuscripts.

When Al Qaeda militants seized control in 2012 they threatened to obliterate the documents.

It fell to a brave band of librarians to save the treasures from destruction.

Journalist and author Joshua Hammer tells their story in the Bad-Ass LIbrarians of Timbuktu, and spoke to the BBC's Katty Kay about the new book.

Edited by Bill McKenna. Produced by Mat Morrison.