I was wondering where these theories come from. So I googled it. It seems radio talk show host, Alex Jones, is a major contributor to these theories. Here's a discussion of that:
https://www.mediamatters.org/blog/20...heories/218163
According to Jones, the FBI recruits mentally ill and mentally disturbed people to be patsies, set up by the FBI to enact terrorist attacks that the FBI can then use as rational to expand the budget and the power of the FBI.