Texas Republican state legislator Rep. Debbie Riddle was not prepared for Anderson Cooper Tuesday night.

Riddle appeared on "Anderson Cooper 360" to discuss the threat of "terror babies" — a supposed threat in which terrorist organizations send pregnant women to the United States to have their children, who would be US citizens but trained and raised abroad to be terrorists and could enter and leave the US without raising suspicion.

Riddle based her claims on her conversations with "former FBI officials" but Cooper demanded evidence.

"What former FBI officials?" he asked. "What evidence is there of some sort of long-term plot to have American babies born here and then become terrorists?

"Well, at this point, I don't have the hard evidence right here in front of me," Riddle responded. She would not reveal her ex-FBI sources or the basis for their claims, and then tried to change the subject to porous borders and the threat of dirty bombs.

"Border security is certainly an issue, and it's a good topic," Cooper said. "It's not the topic, though...I'm just asking for proof. You say you're still gathering it from unnamed former FBI people."

"When your folks called me in the preliminary, that was part of the conversation," Riddle responded. "They did not tell me that you were going to grill me for this specific information that I was not ready to give to you tonight. They did not tell me that, sir. "

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