FBI was warned about Dallas federal court building gunman in 2016

Federal law enforcement officers say the FBI received a tip three years ago about the gunman who opened fire in Downtown Dallas.

Security officers shot and killed Brian Isaack Clyde on Monday after he fired his gun outside the federal building.

An anonymous investigator says a member of Clyde's family called a national tip line in 2016 and said Clyde was suicidal and fascinated with guns. The call apparently came while Clyde was serving in the army. But the caller didn't outline a specific threat and Clyde was not investigated.

Clyde's stepmother, Heather, told FOX 4 that they didn't see any outward signs of what was to come.

"We just want everyone to know that we are as flabbergasted and stunned as everyone else is," she said.

Clyde was discharged from the military in 2017. He got his associates degree in Corpus Christi and then moved back home to North Texas where he landed a job and got his own apartment in Fort Worth.

Heather told FOX 4 that a suicide mission is the only explanation they can come up with for what Clyde did.

"That's our feeling, that he knew there had already been a shooting down there, and he knew that it was a well-armed area. And he didn't seem to have a strategic plan in place. He didn't have real body armor on," she said. "That's really the only thing that we can derive from his actions is that he was [suicidal]. But that's what's driving us crazy is that we'll never really know."

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