According to the documents, in instant messages to the undercover FBI informant, Cornell indicated that while he did not have support to conduct an attack on behalf of any group, "we already got a thumbs up from the Brothers over there and Anwar al Awlaki before his martyrdom and many others." Awlaki was killed by the United States in Yemen in 2011.
In a November meeting with the informant, Cornell said he considered members of Congress to be his enemies, and he outlined a plan to place pipe bombs at and near the U.S. Capitol and use firearms to kill employees and officials inside, according to the documents.
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Federal Bureau of Investigation Acting Special Agent in Charge John Barrios noted that the public was not in danger during this investigation.
Ohio U.S. Republican Senator Rob Portman praised the FBI and other law enforcement agencies for their work "to thwart this potential terrorist act. It is an important reminder of the very real threat that radical Islam continues to pose to the homeland."
The U.S. Capitol Police said they had worked with the FBI on the case.
Cornell has been charged in a federal court in Ohio with attempting to kill a U.S. government officer and possession of a firearm in furtherance of an attempted crime of violence.