Awlaki used 60 email accounts to contact followers including Fort Hood shooter

Fox News:

The American cleric Anwar al-Awlaki used more than 60 email addresses and sent several thousand emails to his followers, some with encryption and code words, while under FBI surveillance -- according to a five-month investigation by Fox News. Some of those emails were exchanged with accused Fort Hood shooter Maj. Nidal Hasan.  

"Fox Files: The Enemy Within," which debuts on Fox News Channel June 15 at 10 p.m. ET, draws on exclusive interviews and first-hand accounts of the Fort Hood massacre which killed 13 and injured at least 43 others on Nov. 5, 2009. For the first time, victims of the shooting, as well as senior investigators, break their silence about the worst act of terrorism on U.S. soil since 9/11.  

"He (Anwar al-Awlaki) was incredibly busy. He -- during his peak period -- had upwards of 60 email accounts that he was using at any given time," retired FBI agent Keith Slotter told Fox Files.  

Slotter, whose career spanned 25 years at the Bureau, was the special agent in charge of the San Diego field office from 2007 to 2012. His agents at the Joint Terrorism Task Force (JTTF), which included detailees assigned to the FBI, tracked the cleric who was the public face of Al Qaeda 2.0 and the new digital jihad.  

Since the attacks of 9/11, there are now more than 100 JTTFs across the country. 

But in the 2011 Senate Homeland Security Committee investigation of the Fort Hood massacre, the FBI came under criticism for failing to act as an "effective interagency information sharing and operation coordination mechanism."    

In other words, at times the FBI failed to share key information with intelligence analysts under their supervision.  

Slotter, who now works at a private international investigative firm specializing in cyber crime and digital forensics, characterized the number as "thousands of emails ... over a three-year period, tens of thousands."  

By 2009, the cleric, the first American on the CIA's kill-or-capture list, understood he was the target of U.S. and foreign intelligence services. Fox Files has learned al-Awlaki shunned the use of phones and turned to his keyboard because he believed email communications were more secure.

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There is much more.

Some of his emails were encrypted.  The information suggest a pretty broad network only some of whom have been killed or captured.  It appears the government is still not communicating with all its agencies over a decade after 9-11.  There has been some attrition of enemy forces which should make it easier to keep up with those remaining on the loose.