They said "they believe, but cannot prove". That is inline with their "Can't know" lines in the past. Just because the system doesn't allow them to identify s

They said "they believe, but cannot prove". That is inline with their "Can't know" lines in the past. Just because the system doesn't allow them to identify sources , is not the same as saying sources are unidentifiable through any means... else the allegations against Bradley Manning would have never occurred.