The FBI arrested a Cincinnati man Wednesday in connection to an alleged terror plot to attack the U.S. Capitol. Christopher Lee Cornell is said to be a supporter of the militant group Islamic State.

CINCINNATI — The father of an Ohio man accused of plotting an attack on the U.S. Capitol is a “mama’s boy who never left the house,” his father says.

Christopher Lee Cornell, 20, who used the Twitter alias Raheel Mahrus Ubayda, was arrested outside a Cincinnati gun store Wednesday after purchasing two automatic weapons and 600 rounds of ammunition.

Authorities say he planned to set off pipe bombs outside the Capitol, then shoot lawmakers and staff as they fled to safety.

Cornell’s father, John, told The Cincinnati Enquirer that his son had converted to Islam in recent years and had found “peace in the religion.”

John Cornell, who said his son is not a violent man, said Christopher frequently endured abuse due to his religious beliefs. He said Christopher lived in his parents’ apartment and worked occasional part-time jobs.

“Everything you’re hearing in the media right now, they’ve already painted him as some kind of terrorist,” John Cornell told the Enquirer. “They’ve painted him as some kind of jihadist. … (Christopher) is one of the most peace-loving people I know.”

The elder Cornell told CNN he believes much of the blame falls on the informant who led the FBI to Christopher Cornell. “I believe he was really vulnerable and I believe he was coerced in a lot of ways,” John Cornell said.

He said he and his wife are heartbroken and love their son more than ever.

“He may be facing life in prison,” John Cornell told CNN. “Do you know how devastating that is?”

FBI Special Agent T.A. Staderman described some details of the alleged plan in the seven-page complaint supporting charges of attempting to kill a U.S. government officer and possession of a firearm.

Federal authorities said the public was never in any danger because investigators were closely monitoring the activities of the suspect during the inquiry.

Tom Willingham, president and CEO of Point Blank Range & Gun Shop in Cincinnati, said he was approached by FBI agents and asked him to help them arrest someone they suspected of wanting to commit a terrorist act on U.S. soil. “Nobody knew enough to be scared,” Willingham told the Enquirer.

After the gun store employees ran Christopher Cornell’s name through the national background check system to ensure he had no criminal record — “Not anyone can come in and buy a gun and walk out,” Willingham said — Cornell bought the rifles and ammunition. He was arrested by the Joint Terrorism Task Force in the parking lot.

Cornell is accused of using cyberspace to plot to assassinate congressional employees and attack the U.S. Capitol for his personal jihad. He was charged with attempted killing of U.S. government officers and possession of firearms in furtherance of an attempted crime of violence.

Christopher Cornell was a wrestler at Cincinnati’s Oak Hills High School, graduating in 2012. Principal John Stoddard issued a statement describing Cornell as a “typical student” who was not a discipline problem.

“His teachers were shocked at the news of his involvement in this situation,” the statement said. “Teachers … remember Christopher as a quiet, but not overly reserved, student who would participate in class and did not withdraw from his class work.”

Schoolmate Jake Flick told NBC News that Cornell began to change during his senior year

“He would say the weirdest stuff about the government,” Flick told NBC, adding that Cornell was very interested in “anarchy.”

Perry and Brennan write for The Cincinnati Enquirer. Contributing: Kevin Johnson, USA TODAY