The FBI sent a bulletin to the Garland, Texas, police three hours before the shooting at the Muhammad cartoon contest, warning law enforcement that one suspect may travel to the event, FBI director James Comey told reporters on Thursday.
Comey said that Elton Simpson, one of the two gunmen in the attack in Garland, mentioned the cartoon contest on Twitter as early as April 23, according to the New York Times.
“We developed information just hours before the event that Simpson might be interested in going to Garland,” Comey told reporters, according to the Times.
Comey said he did not believe that the officers patrolling the event were aware of the FBI’s warning about Simpson.
Garland police spokesman Joe Harn told the Times that he couldn’t comment on the FBI bulletin but said that he did not know that the gunmen were on their way to Garland before the shooting.
“We on the ground had no idea, no information that these guys had left Phoenix and were on their way to Garland,” Harn said.
Though the local police were not aware of a specific threat, authorities prepared extensive security for the event due to previous issues with the American Freedom Defense Initiative, the anti-Islamic group that organized the event.
The FBI operated a command center in Dallas before the cartoon contest to keep track of potential threats to the event, Comey said, according to the Times.
The FBI had been tracking Simpson for a while before he carried out the attack in Garland. The FBI investigated Simpson for potential terrorist connections between 2006 and 2010. Comey said on Thursday that the FBI reopened an investigation a few months before the shooting when Simpson mentioned the Islamic State on Twitter.
Comey told reporters that there are “hundreds, maybe thousands” of individuals in the U.S. who are being contacted by terrorist groups, Comey told reporters, according to USA Today.
He said that the Islamic State has been using social media to contact U.S. citizens, particularly “disturbed people.”
“It’s like the devil sitting on their shoulders, saying ‘kill, kill, kill,”’ Comey said, according to USA Today.
Comey said that the Islamic State’s use of social media makes it harder to track potential threats in the U.S.
