https://www.justice.gov/usao-sdoh/pr/five-men-arrested-charged-plot-attack-kill-government-officials-others-attending
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They planned to fly small drones with explosives to detonate over the north side of the UFC arena, forcing high value targets to evacuate the premises; the group would then act as snipers and shoot these individuals. Before executing the plan, Proper and other conspirators allegedly planned to rendezvous in Fredericksburg, Virginia.
Proper allegedly amassed firearms, thousands of rounds of ammunition, and tactical gear at his home in Ohio, .."