Days before an ISIS sympathizer attacked a cartoon contest in Garland, Texas, he received a text from an undercover FBI agent.

“Tear up Texas,” the agent messaged Elton Simpson days before he opened fire at the Draw Muhammad event, according to an affidavit (pdf) filed in federal court Thursday.

“U know what happened in Paris,” Simpson responded. “So that goes without saying… No need to be direct.”

That revelation comes amidst a national debate about the use of undercover officers and human sources in terrorism cases. Undercover sources are used in more than half of ISIS-related terror cases, according to statistics kept by the George Washington University Program on Extremism, and civil liberties advocates say some of those charged might not have escalated their behavior without those interventions....

The texts were included in the indictment, released Thursday, of Erick Jamal Hendricks of Charlotte, North Carolina. He was charged with conspiring to provide material support to ISIS. The 35-year-old tried to recruit other Americans to form an ISIS cell on secret compounds and introduced an undercover agent to one of the Draw Muhammad attackers, according to the FBI.

But Hendricks did more than make a connection. According to the court papers, he asked the undercover officer about the Draw Muhammad event’s security, size, and police presence, during the event, according to an affidavit filed in court.

The affidavit does not specify what the undercover responded to questions about size and security.

“If you see that pig [Pamela Geller] make your ‘voice’ heard against her,” Hendricks allegedly told the undercover agent, referring to a notorious Islamophobe.

Press officers for the U.S. Attorney’s Office for the Northern District of Ohio, the Cleveland FBI Office, and the Department of Justice declined to comment beyond the affidavit. FBI spokeswoman Carol Cratty hung up on The Daily Beast after being asked about the “tear up Texas” text....