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. 
 
 Christopher Lee Cornell (Photo: Provided/Butler County Jail) 
 
 Federal authorities arrested a Cincinnati man Wednesday in connection with an alleged ISIL-inspired plot to attack the U.S. Capitol. 
 
 Christopher Lee Cornell, 20, who used the alias Raheel Mahrus Ubayda, is accused of revealing the plan to an FBI informant during meetings in Cincinnati where the suspect "discussed his support of ISIL (Islamic State) and waging jihad,'' according to court documents. 
 
 "Christopher Cornell indicated that he considered the members of Congress as enemies and that he intended to conduct an attack on the U.S. Capitol in Washington,'' FBI Special Agent T.A. Staderman said 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 who asked him to help them arrest someone they suspected of wanting to commit a terrorist act on U.S. soil. 
 
 Willingham's employees sold two semi-automatic rifles at about 11 a.m. Wednesday to Cornell. After gun store employees ran his name through the national background check system – "not anyone can come in and buy a gun and walk out," Willingham said – Cornell was sold what Willingham called "sporting rifles." In addition to the M-15 rifles, Cornell bought 600 rounds of ammunition. 
 
 When Cornell left the store and walked to the parking lot. he was arrested by the FBI Cincinnati Joint Terrorism Task Force. 
 
 The U.S. arrest comes during a highly charged period, as French investigators are conducting a search for possible ISIL and al-Qaeda links to last week's deadly attack on the satirical publication Charlie Hebdo. 
 
 Al-Qaeda's franchise in the Arabian Peninsula has claimed credit for the French attack in which the suspects claimed to be acting on behalf of the al-Qaeda group in Yemen. A third suspect claimed allegiance to the Islamic State. The three were killed by French police Friday following tense hostage standoffs. 
 
 The French attacks have fanned anxieties across the globe, including in the U.S., where the FBI Wednesday conducted a national video conference with state and local law enforcement partners to discuss the possible U.S. implications of the assault. 
 
 Among the concerns addressed was whether the Paris attack may mark a significant change in strategy by the al-Qaeda franchise, which had been focused previously on large-scale plots targeting commercial jets and iconic western landmarks. 
 
 The video session, one of the largest such briefings conducted by the FBI, lasted just less than an hour. It was directed by FBI Director James Comey, along with top DHS officials and Washington, D.C., police Chief Cathy Lanier, who discussed the ongoing threat posed by U.S. citizens returning from the conflict in Syria and those inspired by the radical rhetoric spewed by al-Qaeda. 
 
 In the Cincinnati case, which ironically led to the arrest during the conference, Cornell allegedly told the government informant in November that he wanted to travel with the informant to Washington as part of "reconnaissance'' mission to observe the security at government buildings, including the Capitol, before executing the plot. 
 
 The operation, according to court documents, involved the detonation of pipe bombs and the use of firearms to "kill employees and officials in the U.S. Capitol.'' 
 
 While preparing to travel to Washington this week, Cornell was arrested Wednesday following the purchase of two M-15 semi-automatic rifles and 600 rounds of ammunition. 
 
 Rep. Michael McCaul, R-Texas, chairman of the Homeland Security Committee, said the Ohio case "should set off alarm bells'' in wake of the Paris attacks. 
 
 "These terrorists are intent on attacking our country and are attempting to convince Americans at home to radicalize, embrace their perverse world view and commit acts of violence,'' McCaul said. 
 
 Perry reports for the Cincinnati Enquirer 
 
 Read or Share this story: http://usat.ly/1C1UCQ9 ||||| (CNN) For months, 20-year-old Christopher Lee Cornell had been on the FBI's radar. Authorities said he left alarming posts on social media, talking about violent jihad. 
 
 On Wednesday, agents arrested the Cincinnati man before he could put his alleged plot into action. 
 
 Authorities say Cornell, who ostensibly tweeted under the name Raheel Mahrus Ubaydah, hatched a simple scheme. It was similar to the Paris attack on the offices of Charlie Hebdo, but at a key location -- the U.S. Capitol, said a criminal complaint filed by an FBI agent. 
 
 The plan: Set off pipe bombs to put lawmakers and employees in panicked flight and then gun them down with an assault rifle as they ran across his path and that of an accomplice, Special Agent T.A. Staderman wrote. 
 
 Cornell was ready to go, the agent said. 
 
 Christopher Lee Cornell's mugshot from the Butler County Jail in Ohio. 
 
 He had made preparations with a partner. He had researched bomb-making instructions and by Wednesday, Cornell had bought two M-15 rifles with 600 rounds of ammunition. 
 
 But the man Cornell believed was his partner was actually an FBI informant, a man in trouble with the law who worked with the agency to improve his legal standing. 
 
 When they found out Cornell had the weapons, authorities made their move before Cornell could make his. A law enforcement official told CNN that there was never any danger to lawmakers. 
 
 Pounding on the door 
 
 Around lunchtime, more than a dozen agents and local police stood at his parents' house, where he had lived. 
 
 "We heard a pound on the door," John Cornell, Lee Cornell's father, told CNN's Anderson Cooper. Had he not opened it, they would have battered it in with a ram, he said. 
 
 JUST WATCHED Alleged Capitol plotter's father: He's a big mama's boy Replay More Videos ... MUST WATCH Alleged Capitol plotter's father: He's a big mama's boy 04:09 
 
 He had no idea why they were there, and the officers wouldn't tell him, he said. "They just told us they had a search warrant." 
 
 They took the whole family in for questioning. "Where is my son; what is he being charged with?" John Cornell wanted to know. 
 
 "They wouldn't tell us anything," he said. 
 
 The informant, the plan 
 
 In the fall, the informant told the FBI about someone he had been in touch with via Twitter, the criminal complaint said. 
 
 At the end of August, Cornell had allegedly written him an instant message saying the two of them should carry out a lone wolf attack as a way of supporting ISIS. 
 
 He didn't think ISIS or al Qaeda would give them an official sign-off, but he felt he didn't need it. 
 
 "... we already got a thumbs-up from the Brothers over there and Anwar al-Awlaki before his martyrdom and many others," Cornell allegedly wrote. 
 
 Al-Awlaki was a U.S.-born radical cleric associated with Yemen's al Qaeda arm. He was killed in a drone attack in 2011, but his legacy seems to have influence on would-be terrorists around the world. 
 
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 Cornell allegedly told the informant that he had been in contact with people overseas, and that he had aligned himself with ISIS. And he grew closer to the informant. 
 
 "I believe we should meet up and make our own group in alliance with the Islamic State here and plan operations ourselves," Cornell allegedly messaged him. 
 
 Face to face 
 
 The two met twice in person in Cincinnati, the complaint said -- two days in October and two in November. Cornell researched how to build pipe bombs and saved up money to buy weapons and ammunition, the complaint read. 
 
 His father casts doubt on some aspects of the purchase. Cornell was unemployed and worked only seasonally for minimum wage. He was about $500 short of the money needed to make the purchase on his own. 
 
 "He had $1,287 saved up. These guns cost over $1,700," John Cornell said. He thinks someone else had to make up the difference and blames the FBI. He thinks his son was pushed into the plan. 
 
 Cornell wanted to make his "move" in December, the complaint said. He and the informant, posing as his partner, were to travel to Washington, scout out the Capitol and then detonate the bombs and open fire. 
 
 Cornell's journey 
 
 In middle school and high school, Cornell had been a wrestler, his father said. After graduation, he lived at home and was unemployed, not yet knowing what he wanted to do. "He very seldom left the house," John Cornell said. 
 
 "He's a big mama's boy, you know. His best friend is his kitty cat. There's no way he could have carried out any kind of terrorist plot," Cornell's father said. "He didn't even drive; he didn't have a car." 
 
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 He had recently converted to Islam, which gave him inner peace, John Cornell said. 
 
 And he had apparently stopped cutting his beard. On his mugshot at the Butler County Jail, it's long and appears untrimmed. 
 
 But an ISIS follower? 
 
 "Heck no," John Cornell said. "There's no way my son was involved with ISIS." 
 
 Later, he told CNN: "I just want everyone to know that my son is not a monster. I'm not just saying that because he's my son. If I thought he was up to something, I would have beat his butt, and I would have been the first one to turn him in." 
 
 Cornell graduated from Oak Hills High School in 2012, where he was a "typical student," the school district said. 
 
 His teachers remember him as a quiet, but not too shy, student who participated in class. 
 
 "Christopher was not a disruption or a discipline problem in school," the school district said in a statement. "His teachers were shocked at the news of his involvement in this situation." 
 
 According to the local police chief, Cornell had never been in serious trouble before either. 
 
 He protested a ceremony in 2013 to commemorate the September 11, 2001, attacks, holding a sign that read "9/11 was an inside job," Green Township Police Department Chief Bart West told CNN. But he was not arrested or detained. 
 
 Cornell was also a person of interest in a case of vandalism in 2013, the chief said. Again, he was not charged. 
 
 A new friend? 
 
 Cornell made a friend on the Internet, his father believes, and posted comments in defense of Muslims. 
 
 "Chris may have said some things out of anger," John Cornell said. But he has a hard time believing his son encouraged armed jihad. 
 
 Once, after his son stayed out with a friend once for two hours, John Cornell asked him where he'd been. 
 
 "He said that he had went to a mosque," John Cornell said. 
 
 Then Chris moved out quietly. "I never seen him leave," his father said. 
 
 His son left him a note in his former bedroom. It said he had decided to move in with a friend, who had also offered him some work. 
 
 Since his son's arrest, he says he and his wife have not heard anything from officials about where Cornell is. They say they love their son more than ever, and that they are heartbroken. 
 
 "He may be facing life in prison," John Cornell said. "Do you know how devastating that is?"
– A 20-year-old Ohio man arrested yesterday stands accused of plotting to attack the US Capitol with pipe bombs and gunfire. As reported last night, Christopher Lee Cornell was undone by an FBI sting (an undercover operative connected with him after Cornell allegedly posted pro-terror-attack tweets). New details as of this morning, per CNN and USA Today: The alleged plan involved using pipe bombs to force those in the US Capitol to flee; Cornell and his partner were to be armed with assault rifles that would be used to take down officials and employees as they exited the building. The CEO of Cincinnati's Point Blank Range & Gun Shop says the FBI approached him about assisting them, and that store employees sold Cornell two "sporting rifles" and 600 rounds of ammunition yesterday at 11am. Cornell was arrested upon leaving the store. Cornell's "partner," the FBI informant, is described by CNN as "a man in trouble with the law who worked with the agency to improve his legal standing." The two met in person over two two-day periods in Cincinnati, in October and November. The attacks were to be carried out in support of ISIS, says the informant. Cornell's dad isn't buying the gun purchase story, noting that his son was an unemployed seasonal worker who "had $1,287 saved up. These guns cost over $1,700." In his view, the FBI may have provided him with the extra funds. (He does note that his son recently moved out of his house and in with a friend who was going to give him some work.) How dad describes Cornell: "He's a big mama's boy, you know. His best friend is his kitty cat. There's no way he could have carried out any kind of terrorist plot. He didn't even drive; he didn't have a car."