Story highlights Father of suspect says he doesn't think his son "would hurt a fly"

A source says the plan posed no threat to lawmakers; the complaint said it was in its late stages

Christopher Lee Cornell, 20, allegedly aligned himself with ISIS

(CNN) The father of an Ohio man arrested Wednesday for allegedly plotting to attack the U.S. Capitol says his son could never have carried out the plan.

"He's a big mama's boy, you know. His best friend is his kitty cat," John Cornell told CNN's "Anderson Cooper 360."

"There's no way he could have carried out any kind of terrorist plot," the father said. "I think Chris was coerced into a lot of this."

Christopher Lee Cornell, 20, came to the FBI's attention several months ago for alarming social media posts in which he talked about his support for violent jihad, according to a criminal complaint. He allegedly wrote under the alias Raheel Mahrus Ubaydah.

A mug shot of Christopher Lee Cornell in the Butler County Jail in Ohio.

The FBI engaged in an undercover operation, with the help of a person who began cooperating in exchange for favorable treatment on his criminal exposure on an unrelated case.

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