Source: Jerusalem Post, August 12
According to a report in the Daily Mail, among the items found in the Pakistan compound where the former al-Qaida leader was killed by US special forces in 2011 was a 21-page letter warning of the dangers.
In the letter, Bin Laden reportedly called for al-Qaida to sever all ties with the group due to its extreme brutality. He added that ISIS’s blatant disregard for civilian life was likely to damage the reputation of al-Qaida should the groups remain associated. The letter was not written by bin Laden himself, but by a senior al-Qaida official who worked in his service, according to the report.
Making the case for why al-Qaida should distance itself from ISIS, the Daily Mail reported that the letter listed a number of atrocities committed by the group, including the use of chemical weapons, bombing mosques and massacring Catholics in a church in Baghdad.
Eric Koch’s new book, New Beginnings, was launched on September 20. The book is available from 
