WASHINGTON -- Federal investigators knew one of the two gunmen in an attempted attack outside a provocative cartoon contest in Texas might be interested in going to the event, but they had no information he was going to commit violence, FBI director James Comey said Thursday in his first public comments on the Sunday shooting.

The information about Elton Simpson of Phoenix surfaced hours before the contest in Garland, Texas, which the FBI already had identified as a potential target for violence, Comey said.

The director said the agency then sent an intelligence bulletin to the Garland Police Department, including a picture and other information about Simpson, "even though we didn't have reason to believe that he was going to attack the event. In fact, we didn't have reason to believe that he had left Phoenix."

Simpson had been convicted in 2011 after a terrorism-related investigation stemming from what prosecutors said were his plans to travel to Somalia to fight alongside extremists there. The FBI opened a new investigation into his activities in March after suspecting "a renewed interest in jihad" in connection with the Islamic State group, Comey said.

That investigation was "open but far from complete" at the time of the shooting, the FBI director said.

Simpson and his roommate opened fire outside the event but were shot to death before they could kill anyone.