Kevin Johnson

USA TODAY

WASHINGTON — While on bond and subject to electronic monitoring by local police, a 25-year-old Missouri man allegedly began extensive communications with FBI undercover agents about a Presidents' Day plot to attack Kansas City-area rail and bus systems, federal authorities charged Tuesday.

None of the transportation systems was ever at risk during the sting operation, but court documents alleged that Robert Hester, Jr., purchased common bomb-making components — batteries, duct tape, copper wire and roofing nails — before delivering them to an agent posing as a local operative sympathetic to the Islamic State, also called ISIS.

"The undercover employee told Hester that he could 'walk away' (from the plot),'' the court documents state. "But Hester said, 'I'm down,' " allegedly indicating the suspect's support for a plan designed to kill "a lot of people.''

Hester, a U.S. citizen who had received a general discharge from the Army in 2013, allegedly came to the attention of investigators in September through a series of social media posts in which he "expressed his animus towards the U.S., and suggested an adherence to radical Islamic ideology and a propensity for violence.''

Following his October arrest and release on bond while awaiting disposition of an unrelated weapons charge, an undercover FBI agent messaged Hester, allegedly beginning communications that spanned two months.

Even while his whereabouts were being electronically monitored by state authorities, according to court documents, Hester texted the agent and used an encrypted messaging application in which he once expressed his belief that the U.S. government should be "overthrown.''

He later met with the undercover agent, promising to assist in purchasing ammunition for a cache of weapons provided by the agent. Hester, aware that he would be prohibited from personally purchasing the ammunition because of the pending state charges, allegedly told the agent that he would seek the help of a friend and would use proceeds from an expected federal tax refund to finance the purchase.

In a series of alleged electronic communications earlier this month, Hester allegedly expressed his willingness to proceed with the plan which targeted "buses, trains and a train station in Kansas City.''

He was arrested Friday after meeting with another undercover agent where Hester allegedly brought two boxes of roofing nails.

"First on social media, then in face-to-face meetings with an undercover FBI employee, this defendant repeatedly expressed his intent to engage in acts of violent jihad against the United States,'' Missouri U.S. Attorney Tammy Dickinson said Tuesday. "He believed he was part of an ISIS-sponsored terrorist attack that would result in the deaths and injuries of many innocent victims.''

Hester made his initial court appearance Tuesday in Missouri. If convicted, Hester faces a maximum punishment of 20 years in prison and a $250,000 fine.

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