patrick.net

The first attack on U.S. soil for which ISIS claimed responsibility — a 2015 shooting in Garland, Texas — was instigated by the FBI, according to an investigation by CBS' "60 Minutes" and government documents obtained by an attorney involved in the case.

In a macabre twist, an undercover FBI agent who encouraged one of the shooters to "tear up Texas" was also physically present at the scene of the crime, mere feet away from the shooters.

Prior to that, a separate informant was paid $132,000 by the FBI to pretend for three years to be friends with the future shooter. When the man found out his supposed friend had taped more than 1,500 hours of their conversations on behalf of the intelligence agency, he withdrew from his religious community and eventually fell into online religious extremism.

https://www.salon.com/2017/03/30/tear-up-texas-how-the-fbi-played-a-central-role-in-the-first-isis-attack-on-u-s-soil_partner/

Note the shooter was stopped by a security guard, not anybody in the FBI.