attacks like this. and why this mosque, a lot of people may be wondering why isis would attack a mosque in a first place. that's because this mosque was the heart of suffi islam, which is a mystic, more tolerant form of islam than that being practiced by isis and their supporters, their followers, which is more pertanical form of islam and isis views sufis an infidels and they've threatened the sufis before. they've attacked their shrines. so they have been in isis's cross hairs. while no one has claimed responsibility, that's the reason why we believe isis was behind this attack. >> ian lee following the story. thanks for the reporting. let's get some context now from the chair of the department of middle east studies at the london school of economics live this hour from our london bureau. always a pleasure to have you on the show, fuhuage.